Topical NSAIDs for musculoskeletal conditions. A review of the literature

Pharmaceutical residues and caffeine in Arctic fjord waters (west Spitsbergen)

This study examines pharmaceutical residues in the seawater of west Spitsbergen fjords, using indicator compounds that represent different types of medications with various therapeutic uses (sulfamethoxazole, trimethoprim, carbamazepine, diclofenac, and caffeine). Over three years (summer 2018-2021), trimethoprim, carbamazepine, diclofenac, and caffeine were detected in the investigated fjords (Hornsund, Adventfjorden, Grønnfjorden, Isfjorden, and Kongsfjorden), with diclofenac and caffeine being the most common. Sulfamethoxazole was below the limit of detection in all samples. Concentrations reached up to 46.90 ng/L for trimethoprim, 15.00 ng/L for carbamazepine, 8.40 ng/L for diclofenac, and 589.9 ng/L for caffeine. The results indicate that both insufficient wastewater management and cruise ships or other vessels should be considered as potential causes of the presence of pharmaceuticals and caffeine. Ecological risk assessment revealed predominantly low-risk concentrations, except for diclofenac, where the risk of adverse effects on biota was assessed as medium. The obtained results emphasize the importance of continuous monitoring and management to mitigate potential adverse effects in the marine Arctic.

Formulation of Microemulsion-Based Gels for Enhanced Topical Administration of Nonsteroidal Anti-Inflammatory Drugs

Nonsteroidal anti-inflammatory drugs are commonly administered orally to manage pain and inflammation, but they can have negative gastrointestinal side effects. Topical delivery is an alternative, and microemulsions (μEs) have been shown to be effective in facilitating, but they suffer from a liquid nature and low long-term retention on the skin. Hence, microemulsified gels (μEGs) have been developed, and in this study, we explored certain μEGs with diclofenac sodium (DF-Na) and naproxen sodium (NP-Na) with the hypothesis to ensure a slower and more sustained delivery of NSAIDs through the skin. The μEGs comprised castor oil (∼8%), water (∼12%), Tween-20 (∼72%), Span-20 (∼8%), poloxamer 407, and DF-Na or NP-Na. Optical microscopy was used to study the microstructures in the μEs and μEGs, and phase transitions from water-in-oil (w/o) to oil-in-water (o/w) with continuous networks were observed. Based on studies with dynamic light scattering and analyses of electron micrographs, it was observed that the μEs and μEGs loaded with DF-Na and NP-Na comprised monomodal nanodroplets. The average sizes of the droplets were (∼35 nm) and (∼60 nm) for the μEGs, without and with drugs. Fluorescence spectroscopy was used to ensure that the drugs were more likely to be present in the hydrophobic microenvironment of the formulations. Moreover, ex vivo permeation studies were conducted at pH values of 5.5 and 7.4 across rabbit skin. The release rates of DF-Na (>99 ± 1.5%, P < 0.07) and NP-Na (>89 ± 1.1%, P < 0.01) were slower for the μEGs within 8-10 h than for the μEs at the low pH, which is of relevance to the optimal pH of the skin. It was observed that μEGs with high viscosities are effective and may have potential for use in topical drug delivery applications.

Induction of Semaphorin 3A by Resveratrol and Pinostilbene via Activation of the AHR-NRF2 Axis in Human Keratinocytes

Semaphorin 3A (SEMA3A), a nerve-repellent factor produced by keratinocytes, has an inhibitory effect on nerve extension to the epidermis. Epidermal innervation is involved in pruritus in inflammatory skin diseases such as atopic dermatitis (AD) and dry skin. We previously reported that tapinarof, a stilbene molecule, upregulates SEMA3A in human keratinocytes. We also showed that this mechanism is mediated via the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, and the nuclear factor erythroid 2-related factor 2 (NRF2) axis. Since some stilbenes activate AHR and NRF2, we attempted to identify other stilbenes that upregulate SEMA3A. We analyzed normal human epidermal keratinocytes (NHEKs) treated with 11 types of stilbenes and examined SEMA3A expression. We found that resveratrol and pinostilbene, antioxidant polyphenols, upregulated SEMA3A and increased nuclear AHR and NRF2 expression. In addition, AHR knockdown by small interfering RNA (siRNA) transfection abolished the NRF2 nuclear expression. Furthermore, AHR and NRF2 knockdown by siRNA transfection abrogated resveratrol- and pinostilbene-induced SEMA3A upregulation. Finally, we confirmed that resveratrol and pinostilbene increased SEMA3A promoter activity through NRF2 binding using ChIP-qPCR analysis. These results suggest that resveratrol and pinostilbene upregulate SEMA3A via the AHR-NRF2 axis in human keratinocytes.

Comparative evaluation of efficacy of diclofenac and ketoprofen administered using transdermal drug delivery route in management of post endodontic pain: A randomized controlled clinical trial

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used as a postoperative medication after endodontic treatment. The introduction of transdermal patches aided in reducing the discomfort caused by medication prescribed through the oral route.

Aim

This study aims to compare the efficacy of transdermal patches of diclofenac and ketoprofen for postendodontic pain control.

Materials and Methods

Thirty patients with symptomatic irreversible pulpitis in singlerooted teeth of either arch were endodontically treated by a single endodontist. Oral diclofenac for Group I and transdermal diclofenac patch for Group II and transdermal ketoprofen patch for Group III were administered as postendodontic analgesics. Visual Analog Scale chart was used to record pain intensity preoperatively and at intervals of 4, 8, and 24 h postoperatively. Paracetamol 500 mg tablets were provided as rescue medication.

Statistical Analysis

Repeated Measure ANOVA.

Results

There was a significant decrease in the postoperative pain intensity scores for both transdermal groups. The postoperative scores gradually decreased from day 1 to day 2. Six out of ten patients who had received diclofenac tablets complained of gastric discomfort.

Conclusion

Both transdermal ketoprofen and diclofenac patches were effective than oral diclofenac tablet and can be used as an alternative and effective analgesic for postendodontic pain management, especially in patients with gastric discomfort.

Enzymes for dermatological use

Skin is the ultimate barrier between body and environment and prevents water loss and penetration of pathogens and toxins. Internal and external stressors, such as ultraviolet radiation (UVR), can damage skin integrity and lead to disorders. Therefore, skin health and skin ageing are important concerns and increased research from cosmetic and pharmaceutical sectors aims to improve skin conditions and provide new anti-ageing treatments. Biomolecules, compared to low molecular weight drugs and cosmetic ingredients, can offer high levels of specificity. Topically applied enzymes have been investigated to treat the adverse effects of sunlight, pollution and other external agents. Enzymes, with a diverse range of targets, present potential for dermatological use such as antioxidant enzymes, proteases and repairing enzymes. In this review, we discuss enzymes for dermatological applications and the challenges associated in this growing field.

Cost-utility Analysis of Anterior Cervical Discectomy and Fusion for Cervical Spondylosis Patients Comparing Polyetheretherketone Versus Tricortical Iliac Crest Bone Graft

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

To perform a cost-utility analysis and to investigate the clinical outcomes and patient's quality of life after anterior cervical discectomy and fusion (ACDF) to treat cervical spondylosis compared between fusion with polyetheretherketone (PEEK) and fusion with tricortical iliac bone graft (IBG) in Thailand.

SUMMARY OF BACKGROUND DATA

ACDF is one of the standard treatments for cervical spondylosis. The fusion material options include PEEK and tricortical IBG. No previous studies have compared the cost-utility between these 2 fusion material options.

PATIENTS AND METHODS

Patients with cervical spondylosis who were scheduled for ACDF at Siriraj Hospital (Bangkok, Thailand) during 2019-2020 were prospectively enrolled. Patients were allocated to the PEEK or IBG fusion material group according to the patient's choice of fusion material. EuroQol-5 dimensions 5 levels and relevant costs were collected during the operative and postoperative periods. A cost-utility analysis was performed using a societal perspective. All costs were converted to 2020 United States dollars (USD), and a 3% discount rate was used. The outcome was expressed as the incremental cost-effectiveness ratio.

RESULTS

Thirty-six patients (18 ACDF-PEEK and 18 ACDF-IBG) were enrolled. Except for Nurick grading, there was no significant difference in patient baseline characteristics between groups. The average utility at 1 year after ACDF-PEEK and ACDF-IBG were 0.939 ± 0.061 and 0.798 ± 0.081, respectively ( P < 0.001). The total lifetime cost of ACDF-PEEK and ACDF-IBG was 83,572 USD and 73,329 USD, respectively. The incremental cost-effectiveness ratio of ACDF-PEEK when compared with that of ACDF-IBG showed a gain of 4468.52 USD/quality-adjusted life-years, which is considered cost-effective at the Thailand willingness-to-pay threshold of 5115 USD/quality-adjusted life-year gained.

CONCLUSIONS

ACDF-PEEK was found to be more cost-effective than ACDF-IBG for treating cervical spondylosis in Thailand.

LEVEL OF EVIDENCE

Level II.

Evaluation of the Efficacy of Regional Anesthesia and Intramuscular Diclofenac in the Management of Postoperative Pain: A Comparative Study

Aim:

Managing postoperative pain following maxillofacial surgery is an important task. Our study aims to compare this with regional anesthesia or IM diclofenac.

Materials and Methods:

This study included 30 patients who underwent bi-jaw orthognathic surgery between April 2016 and January 2020. Two groups were formed. Group A was administered inferior alveolar nerve block at the surgical site bilaterally using 0.5% ropivacaine and Group B were administered 75 mg intramuscular diclofenac just before extubation. Tramadol HCl 2 mg/kg body wt is used as a rescue analgesic. The pain was evaluated periodically at 2^nd, 4^th, 6^th, and 12 h postoperatively.

Results:

The mean Visual Analog Scale score was 2 in Group A and 5 in Group B. The mean duration of analgesia was 6 h 42 min, whereas in Group B, it was 8 h and 5 min. In 2 patients (13.3%) belonging to Group A and 3 patients (20%) belonging to Group B. There were no local complications in any group.

Conclusion:

It was observed that regional anesthesia in the form of intraoral nerve blocks was efficient than diclofenac (75 mg) administered intramuscularly for the management of immediate postoperative pain.

Expert consensus of the Chinese Association for the Study of Pain on pain treatment with the transdermal patch

Chronic pain lasting more than 3 mo, or even several years can lead to disability. Treating chronic pain safely and effectively is a critical challenge faced by clinicians. Because administration of analgesics through oral, intravenous or intramuscular routes is not satisfactory, research toward percutaneous delivery has gained interest. The transdermal patch is one such percutaneous delivery system that can deliver drugs through the skin and capillaries at a certain rate to achieve a systemic or local therapeutic effect in the affected area. It has many advantages including ease of administration and hepatic first pass metabolism avoidance as well as controlling drug delivery, which reduces the dose frequency and side effects. If not required, then the patch can be removed from the skin immediately. The scopolamine patch was the first transdermal patch to be approved for the treatment of motion sickness by the Food and Drug Administration in 1979. From then on, the transdermal patch has been widely used to treat many diseases. To date, no guidelines or consensus are available on the use of analgesic drugs through transdermal delivery. The pain branch of the Chinese Medical Association, after meeting and discussing with experts and based on clinical evidence, developed a consensus for promoting and regulating standard use of transdermal patches containing analgesic drugs.

Efficacy of topical interventions for temporomandibular disorders compared to placebo or control therapy: a systematic review with meta-analysis

This systematic review focused on the efficacy of topical products in reducing temporomandibular joint disorder (TMD)-associated pain, in comparison to placebo or control interventions. The EMBASE, Web of Science, Cochrane Library, and MEDLINE via PubMed databases were searched for randomized controlled trials (RCTs) using topical interventions in adults diagnosed with TMD. The pain intensity was the primary outcome, and other clinical findings were the secondary outcomes. The risk of bias was evaluated according to the Cochrane's handbook. The search up to February 7, 2020 identified a total of 496 unduplicated references. Nine RCTs with 355 adult patients diagnosed with TMD were included. The meta-analysis did not show a significant reduction in baseline pain intensity in the nonsteroidal anti-inflammatory drug (NSAIDs) group, when compared to the placebo group (P = 0.288). One study demonstrated a statistically significant pain score decrease for Theraflex-TMJ compared to placebo after 10 d of treatment (P = 0.003) and follow-up, 5 d after the last application (P = 0.027). Ping On reduced pain at 4 weeks of application (P < 0.001) but not after 7 d of application (P = 0.136). In one study, cannabidiol (CBD) significantly improved the pain intensity compared to placebo (P < 0.001). However, no differences were found with capsaicin in the two studies (P = 0.465). Evidence was of low quality because the studies were considered as having an unclear or a high risk of bias and a small number of studies were analyzed. The evidence is not sufficient to support the use of topical NSAIDs and capsaicin, and limited evidence was found for Threraflex-TMJ, bee venom, Ping On, and CBD, with only one study reporting for each. Additional studies are recommended to validate these results.

Efficacy of Transdermal Diclofenac Patch as an Analgesic Following Premolar Extractions in Orthodontic Patients

Aim

The aim of the study was to evaluate the efficacy of transdermal diclofenac patch versus oral diclofenac tablet as analgesic following premolar extractions in orthodontic patients.

Materials and Methods

Thirty-three symmetrical pairs of indicated premolars (either first or second) were included for the present study. Each patient was given either transdermal diclofenac sodium patch 100 mg once a day or oral diclofenac tablet 50 mg twice a day for 3 days after the extraction. Pain was assessed by a 10-point visual analog scale and 4-point verbal rating scale given to the patient for each day for 3 days after the extraction. All observational findings were recorded, tabulated, and analyzed statistically.

Results

This study consisted of 33 patients with a mean age of 18.73 ± 3.677 years. Out of 33 patients included in this study, 5 were male and 28 were female. The result of the study showed that consecutive postoperative days transdermal diclofenac patch was slightly more efficient in controlling the postoperative pain in the extraction done for the orthodontic purpose than diclofenac oral tablet, however statistically no significant difference was observed using Chi-square test (P > 0.05).

Conclusion

Transdermal diclofenac patch showed potential analgesic modality for the management of mild-to-moderate intensity pain in premolar orthodontic extraction, with lower incidence of systemic adverse effects. However, cost and availability may limit the use of transdermal patch.

Topical agents: a thoughtful choice for multimodal analgesia

For over a thousand years, various substances have been applied to the skin to treat pain. Some of these substances have active ingredients that we still use today. However, some have been discontinued due to their harmful effect, while others have been long forgotten. Recent concerns regarding the cardiovascular and renal risk from nonsteroidal anti-inflammatory drugs, and issues with opioids, have resulted in increasing demand and attention to non-systemic topical alternatives. There is increasing evidence of the efficacy and safety of topical agents in pain control. Topical analgesics are great alternatives for pain management and are an essential part of multimodal analgesia. This review aims to describe essential aspects of topical drugs that physicians should consider in their practice as part of multimodal analgesia. This review describes the mechanism of popular topical analgesics and also introduces the most recently released and experimental topical medications.

Comparison of Safety, Efficacy, Patient Compliance and Cost-Effectiveness of Transdermal, Oral and Intramuscular Diclofenac for Pain Control Following Oral Surgical Procedures

Purpose

To evaluate transdermal diclofenac in terms of analgesic efficacy, safety, compliance and cost-effectiveness and to compare it with oral tablets and intramuscular (IM) injections following surgical removal of impacted mandibular third molars.

Subjects and Methods

A prospective, single-centre, multi-arm parallel, randomized study on subjects undergoing extraction of impacted mandibular third molars was conducted between January 2016 and December 2017. The study included 90 participants, 30 in each group. Participants received the standard once daily (OD) dosages of diclofenac in each group for three post-operative days and were advised to consume paracetamol 500 mg as rescue analgesics if the pain was not alleviated. Outcome measures such as demographics, duration of surgery, post-operative pain, the number of rescue analgesics taken, adverse drug reactions experienced and overall global assessment for three post-operative days were recorded by the participants on a questionnaire.

Results

Transdermal and oral forms achieved similar analgesia on all 3 days. Injectable diclofenac had significantly better pain control on the second and third post-operative days compared to tablets and on the third day compared to transdermal diclofenac. A higher number of rescue analgesics was consumed in oral group on day 1. Gastritis and vomiting were seen in 36.66% and 10% cases, respectively, in oral group. 100% of those in IM group had pain on injection. 6.6% complained of dry skin due to patch, while 3.33% had rash and pruritus. Transdermal group had better overall global assessment by patients with 16.67%, 46.67% and 20% participants reporting excellent, very good and good pain control, respectively. The cost in INR was maximum for the transdermal group.

Conclusion

Transdermal diclofenac is an excellent alternative to oral and parenteral routes of drug administration in oral surgical procedures with adequate analgesic efficacy, good compliance and fewer side effects.

Efficacy of diclofenac & thiocolchioside gel phonophoresis comparison with ultrasound therapy on acute low back pain; a prospective, double-blind, randomized clinical study

PURPOSE

To investigate the effect of Phonophoresis (PP) with the combination of nonsteroidal anti-inflammatory drugs (NSAID's) and myorelaxant versus routine Ultrasound (US) treatment with non-therapeutic gel on the patients with acute low back pain (ABP).

METHODS

Sixty patients with ABP were randomly assigned into 2 groups. In Group 1 (n = 30) US was applied using diclofenac + Thiocolchicoside gel for 10 min and for a total of 10 sessions. In Group 2 (n = 30) the same US protocol was applied with the same setting and timing with Group 1 using US gel that does not contain any pharmaceutical ingredient. Evaluation parameters were Visual numeric scale (VNS), Oswestry Disability Index (ODI), and Shober test.

RESULTS

Comparison of the results obtained from the two groups before treatment and at second (W2) and sixth weeks (W6) posttreatment showed significant improvement in all parameters in both groups (p < 0.05). Comparison of the groups showed significantly superior improvement in Group 1 for ODI while there was no difference in other parameters at W2. At W6, there was significantly superior improvement in all parameters (p < 0.05) except for Shober test in Group1.

CONCLUSION

Our results showed that PP treatment is superior than conventional US therapy at short term in ABP patients.

Relative efficacy and safety of topical non-steroidal anti-inflammatory drugs for osteoarthritis: a systematic review and network meta-analysis of randomised controlled trials and observational studies

Objectives

To compare the efficacy and safety of topical non-steroidal anti-inflammatory drugs (NSAIDs), including salicylate, for the treatment of osteoarthritis (OA).

Methods

PubMed, Embase, Cochrane Library and Web of Science were searched from 1966 to January 2017. Randomised controlled trials (RCTs) comparing topical NSAIDs with placebo or each other in patients with OA and observational studies comparing topical NSAIDs with no treatment or each other irrespective of disease were included. Two investigators identified studies and independently extracted data. Bayesian network and conventional meta-analyses were conducted. The primary outcomes were pain relief for RCTs and risk of adverse effects (AEs) for observational studies.

Results

43 studies, comprising 36 RCTs (7 900 patients with OA) and seven observational studies (218 074 participants), were included. Overall, topical NSAIDs were superior to placebo for relieving pain (standardised mean difference (SMD)=−0.30, 95% CI −0.40 to –0.20) and improving function (SMD=−0.35, 95% CI −0.45 to –0.24) in OA. Of all topical NSAIDs, diclofenac patches were most effective for OA pain (SMD=−0.81, 95% CI −1.12 to –0.52) and piroxicam was most effective for functional improvement (SMD=−1.04, 95% CI −1.60 to –0.48) compared with placebo. Although salicylate gel was associated with higher withdrawal rates due to AEs, the remaining topical NSAIDs were not associated with any increased local or systemic AEs.

Conclusions

Topical NSAIDs were effective and safe for OA. Diclofenac patches may be the most effective topical NSAID for pain relief. No serious gastrointestinal and renal AEs were observed in trials or the general population. However, confirmation of the cardiovascular safety of topical NSAIDs still warrants further observational study.

A comparative evaluation of diclofenac sodium transdermal patch, oral diclofenac sodium with intramuscular injections of diclofenac sodium in patients suffering from oral pain: A randomized control trial

Background:

Newer drug delivery systems such as transdermal patches using pain relieving or modifying agents emerged as a mainstream treatment protocol for management of pain on the outpatient basis. The administration of diclofenac 100 mg in the transdermal patch in the patients having dental pain due to periapical/periodontal infections was evaluated.

Materials and Methods:

Ninety patients of either gender, between 18 and 80 years were divided into 3 groups (Group A - oral medication, Group B - transdermal patch, Group C - intramuscular group). Patients at the Dental Department with pain from periapical/periodontal pathologies were explained about the procedure of analgesia. With written consent, 100 mg diclofenac sodium transdermal patches were prescribed to patients who opted their use in pain control for 2 consecutive days. A visual analog scale was provided for all patients assessing the pain intensity during the study.

Results:

Significant difference in the mean percentage reduction in visual analog scale (VAS) score among the three groups at day 1 and 2 (P < 0.001). Post hoc test showed that intramuscular (IM) and oral groups had significantly higher mean VAS score than patch group.

Conclusion:

Diclofenac administered through oral and IM routes showed significant improvement in pain relief when compared to the transdermal route. However, diclofenac transdermal patches have shown significant improvement in VAS score between the baseline and consecutive days and can be used in mild pain with lower adverse events.

A comparison of transdermal over-the-counter lidocaine 3.6% menthol 1.25%, Rx lidocaine 5% and placebo for back pain and arthritis

Aim: Transdermal lidocaine therapy has become a gold standard as part of a treatment regimen for patients who suffer from localized pain. We compared transdermal patches: over-the-counter (OTC) lidocaine 3.6% combined with menthol 1.25%, prescription lidocaine 5% (Rx) and placebo. Methods: In a double-blind, placebo-controlled trial, 87 patients were randomized to: OTC, Rx or placebo. Results: OTC met primary end points of noninferiority compared with Rx for efficacy, side effects and quality of life. Versus placebo, OTC proved superiority for efficacy, general activity and normal work. Side effects were similar. Conclusion: It is theorized that menthol's ability to increase skin permeability facilitated more efficient drug delivery to the site of pain causing higher than expected efficacy. Decreased cost and resource utilization could benefit patients and payers.

Salicylate Poisoning Potential of Topical Pain Relief Agents: From Age Old Remedies to Engineered Smart Patches

The pain relief capabilities of methyl salicylate are well established and a multitude of over-the-counter products populate pharmacy shelves. Over-application of the topical preparation containing the drug, or its accidental ingestion, invariably result in salicylate poisoning and in severe cases can be fatal. The drug has been a regular feature of the US National Poison Database Survey over the past decade and continues to pose a risk to children and adults alike. The aim of the review has been to cast a spotlight on the drug and assess why its use remains problematic, how technology could offer more efficacious delivery regimes, and minimise the possibility of accidental or intentional misuse.

Thermo conductive carbon nanotube-framed membranes for skin heat signal-responsive transdermal drug delivery

Smart carbon nanotube (CNT)-framed (SCNF) membranes were prepared by self-assembly of highly thermo conductive CNT molecules hybridized with chitosan (Chit) in a core–shell structure and then by chemical integration of a temperature-responsive copolymer, poly(NIPAAm-co-BVIm) (or pNIBIm), as an additional outer shell.

Is there any role for topical non-steroidal anti-inflammatory drugs in the treatment of mild to moderate musculoskeletal pain in a Lebanese community pharmacy?

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely prescribed in the community pharmacy. Their systemic administration has been related to significant adverse effects. The aim of this study was to evaluate the efficacy of topical NSAIDs in managing mild to moderate musculoskeletal pain versus systemic administration or combination of both routes.

METHODS

This was a prospective observational study conducted in a large Lebanese community pharmacy over a period of 5 months in 302 patients. Participants were divided into three groups according to their route of administration of NSAIDs either topically, systemically or combination of both. During follow up period, degree of pain, efficacy of NSAID therapy, side effects, onset time and duration of pain relief reported by each patient were collected by the study investigators using specific formulated questionnaire. Degree of pain was assessed using the Numeric Rating Scale (NRS-11). The efficacy of NSAID therapy was defined as 50 % reduction or more in pain. The primary outcome was to assess the efficacy between groups. The secondary outcomes were onset time, duration of pain relief and side effects between the three groups.

RESULTS

A total of 149 patients were enrolled in this study. 78 patients administered topical NSAIDs, 40 administered systemic NSAIDs and 31 administered combination of both routes. Efficacy of NSAID therapy for all routes was reported in 132 participants (89 %) distributed as 64 in topical, 37 in systemic and 31 in combination. Bi-variate analysis showed no significant difference in efficacy between topical versus systemic (p = 0.99) and topical versus combination (p = 0.14). The mean onset of topical NSAIDs was significantly faster than systemic by 12.7 min (p < 0.05). The mean duration of pain relief of systemic NSAIDs was significantly longer than topical by 3 h (p < 0.05). Patients administered systemic NSAIDs (either alone or in combination) reported increase in blood pressure and gastric-upset 8 and 38 cases, respectively.

CONCLUSION

There was no significant statistical difference between NSAIDs route's of administration for the treatment of mild to moderate musculoskeletal pain in Lebanese community pharmacy patients. Topical NSAIDs were fast in onset and effective in reducing pain with no significant adverse effects.

Knowledge and Use of, and Attitudes toward, Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) in Practice: A Survey of Ontario Physiotherapists

Purpose: To investigate Ontario physiotherapists' knowledge and use of, and attitudes toward, non-steroidal anti-inflammatory drugs (NSAIDs) to identify whether there is a need for physiotherapists to receive education specific to NSAIDs. Method: An existing survey instrument was modified and tested by five Ontario physiotherapists. The final version was distributed electronically to approximately 4,400 Ontario Physiotherapy Association members as a self-administered online questionnaire. Results: A total of 294 physiotherapists responded to the survey (response rate=6.7%). Respondents demonstrated variability in their knowledge of NSAID contraindications, side effects, and drug interactions. Most respondents (62.6%) were incorrect or unsure about where and how to obtain most NSAIDs, and most demonstrated incorrect or uncertain knowledge of the relevant legislation. Despite this lack of knowledge, 50% of respondents recommend NSAIDs to their patients. Conclusions: Many Ontario physiotherapists who participated in this survey recommend NSAIDs to their patients despite having a variable understanding of the legislation and medication-related factors. A lack of thorough knowledge of risks and contraindications has implications for patient safety. Physiotherapists who incorporate medications into their practice should access comprehensive information on appropriate NSAID use and should inform themselves about legislative restrictions to ensure that associated treatment is provided in a manner that is evidence based, safe, and in keeping with regulatory boundaries.

Diclofenac Transdermal Patch: A Potential Ingress to Maxillofacial Surgery

PURPOSE

To evaluate the analgesic efficacy of a diclofenac transdermal patch with diclofenac intra muscular injection in the immediate postoperative period in patients undergoing major oral surgical procedures.

MATERIALS AND METHODS

Subjects who underwent bijaw surgeries for surgical correction of various dentofacial deformities were included. Sixty such patients who belonged to the above entity were randomly categorized into two groups from Jan 2012-Aug 2015. Group A (study group) received a single dose of 100 mg transdermal diclofenac patch, Group B (control group) received 75 mg intramuscular diclofenac and tramadol HCl 2 mg/kg body wt was used as rescue analgesic in the immediate post operative phase. The analgesic efficacy of the drugs are evaluated on periodic patient's perception of pain in the immediate postoperative phase of 2nd, 6th, 12th, 24th and 48 hours.

RESULTS

The mean VAS score in Group A was 2, mean duration of analgesia was 16 h 9 min, and in Group B the mean VAS score was 4, duration of analgesia was 8 h and 4 min. Tramadol HCl was given as rescue analgesia in 22 % (6) of patients belonging to Group A. None of the patients from both the groups reported local complications.

CONCLUSION

A noninvasive application of a single dose of 100 mg transdermal diclofenac patch is more effective than intramuscular diclofenac (75 mg) in the immediate post operative phase, without any significant side-effects is a novel ingress into the field of oral and maxillofacial surgery for post operative pain management.

Fate of pharmaceuticals in full-scale source separated sanitation system

Removal of 14 pharmaceuticals and 3 of their transformation products was studied in a full-scale source separated sanitation system with separate collection and treatment of black water and grey water. Black water is treated in an up-flow anaerobic sludge blanket (UASB) reactor followed by oxygen-limited autotrophic nitrification-denitrification in a rotating biological contactor and struvite precipitation. Grey water is treated in an aerobic activated sludge process. Concentration of 10 pharmaceuticals and 2 transformation products in black water ranged between low μg/l to low mg/l. Additionally, 5 pharmaceuticals were also present in grey water in low μg/l range. Pharmaceutical influent loads were distributed over two streams, i.e. diclofenac was present for 70% in grey water, while the other compounds were predominantly associated to black water. Removal in the UASB reactor fed with black water exceeded 70% for 9 pharmaceuticals out of the 12 detected, with only two pharmaceuticals removed by sorption to sludge. Ibuprofen and the transformation product of naproxen, desmethylnaproxen, were removed in the rotating biological contactor. In contrast, only paracetamol removal exceeded 90% in the grey water treatment system while removal of other 7 pharmaceuticals was below 40% or even negative. The efficiency of pharmaceutical removal in the source separated sanitation system was compared with removal in the conventional sewage treatment plants. Furthermore, effluent concentrations of black water and grey water treatment systems were compared with predicted no-effect concentrations to assess toxicity of the effluent. Concentrations of diclofenac, ibuprofen and oxazepam in both effluents were higher than predicted no-effect concentrations, indicating the necessity of post-treatment. Ciprofloxacin, metoprolol and propranolol were found in UASB sludge in μg/g range, while pharmaceutical concentrations in struvite did not exceed the detection limits.

Enhancing Skin Permeation of Biphenylacetic Acid (BPA) Using Salt Formation with Organic and Alkali Metal Bases

In the present study, a series of organic and alkali metal salts of biphenylacetic acid (BPA) have been prepared and evaluated in vitro for percutaneous drug delivery. The physicochemical properties of BPA salts were determined using solubility measurements, DSC, and IR. The DSC thermogram and FTIR spectra confirmed the salt formation with organic and alkali metal bases. Among the series, salts with organic amines (ethanolamine, diethanolamine, triethanolamine, and diethylamine) had lowered melting points while the alkali metal salt (sodium) had a higher melting point than BPA. The in vitro study showed that salt formation improves the physicochemical properties of BPA, leading to improved permeability through the skin. Amongst all the prepared salts, ethanolamine salt (1b) showed 7.2- and 5.4-fold higher skin permeation than the parent drug at pH 7.4 and 5.0, respectively, using rat skin.

Comparison of benzydamine hydrochloride and Salvia officinalis as an adjuvant local treatment to systemic nonsteroidal anti-inflammatory drug in controlling pain after tonsillectomy, adenoidectomy, or both: an open-label, single-blind, randomized clinical trial

BACKGROUND

Benzydamine hydrochloride (BNZD) is a nonsteroidal anti-inflammatory drug (NSAID) used in an oral rinse formulation as an adjuvant to other NSAIDs in controlling postoperative pain after tonsillectomy, adenoidectomy, or both. Salvia officinalis (SO) is a topically applied herbal preparation frequently used for the same indication. Pain, bleeding, and infection are the most common postoperative complications of tonsillectomy.

OBJECTIVE

The aim of this study was to compare the efficacy and tolerability of BNDZ with those of SO as adjuvant treatments in controlling postoperative pain.

METHODS

This open-label, single-blind, randomized clinical trial was conducted at the Department of Otorhinolaryngology, Clinical Hospital Center "Dr. Dragiša Mišović-Dedinje" (Belgrade, Serbia and Montenegro). Pediatric and adult patients undergoing tonsillectomy, adenoidectomy, or both were enrolled. Patients were randomized to receive BNZD or SO, in addition to ibuprofen 20 mg/kg·d (children) or diclofenac 100 mg/d (adults). The primary end point was the proportion of patients with mild or no pain on postoperative days 1, 2, 4, and 7. Secondary end points were the incidences of infection, hemorrhage, and other adverse events.

RESULTS

A total of 420 patients were enrolled (217 females, 203 males; 278 children, 142 adults; mean [SD] age, 6.2 [2.1] years [children] and 24.1 [9.8] years [adults] [range, 3-45 years]). One hundred thirty-eight children received BNZD; 140 received SO (both in addition to ibuprofen 20 mg/kg·d). Seventy-two adults received BNZD; 70 received SO (both in addition to diclofenac 100 mg/d). A significantly lower proportion of children treated with adjuvant BNZD experienced moderate or severe pain than those treated with SO at each time point (P < 0.01 at days 1 and 4; P < 0.001 at days 2 and 7). In children, the risk for postoperative infection was similar between BNZD and SO (absolute risk reduction [ARR], 6.9%; 95% CI, 6.4%-7.6%); however, the risk was reduced in adults (ARR, 19.0%; 95% CI, 16.5%-21.9%; P = 0.008).

CONCLUSIONS

In this clinical trial of children and adults who underwent tonsillectomy, adenoidectomy, or both, BNZD, as an adjuvant to an NSAID, was more effective than SO in controlling postoperative pain and infection. The pain-reducing effect of BNZD was of quick onset and persisted for 1 week after surgery. The safety profile of BNZD was comparable to that of SO, with the exception of postoperative infection in adults, for which BNZD was more efficacious. In particular, the use of BNZD was not associated with a high risk for early postoperative hemorrhage.

Comparison of transdermal diclofenac patch with oral diclofenac as an analgesic modality following multiple premolar extractions in orthodontic patients: A cross over efficacy trial

Aims:

This study was performed to compare the degree of post operative analgesia, patient compliance, and frequency of adverse events with the use of oral diclofenac tablets and transdermal diclofenac patch following multiple premolar extractions in patients undergoing orthodontic treatment.

Materials and Methods:

Twenty young pre-orthodontic patients requiring bilateral maxillary and mandibular first premolar extractions were selected for the study. The right maxillary and mandibular first premolars were extracted first and 50 mg oral diclofenac sodium tablets were prescribed to be taken thrice a day for three days. In the next appointment, the contralateral first premolars were extracted and a 100 mg transdermal diclofenac patch was applied once a day for three days. Pain relief and pain intensity with both the diclofenac formulations was recorded for each of the three postoperative days using 5-point Verbal Pain Intensity and Pain Relief Score Charts.

Results and Conclusions:

Statistical analyses revealed that there was a gradual increase in pain relief scores and a gradual decrease in pain intensity scores with the use of oral diclofenac tablets as well as with the transdermal patch. However, subjects reported that they were more comfortable using the transdermal patch particularly due to the once-a-day application and lesser frequency of systemic adverse effects. Results of this study indicate that the transdermal diclofenac patch provides as potent analgesia as the oral diclofenac tablets with the added advantage of better patient compliance and may be used for routine post extraction analgesia.

A microdialysis study of topically applied diclofenac to healthy humans: Passive versus iontophoretic delivery

Topical application of NSAIDs is an alternative route to systemic administration when a local anti-inflammatory effect of the underlying tissue is a treatment option. The aim of the present microdialysis study was to assess and compare plasma and tissue levels of diclofenac when topically applied with or without iontophoresis in healthy adults. Fourteen healthy adults (26±9.4 years) were randomized to diclofenac applied by iontophoresis, or by a gel, in a crossover design. Diclofenac concentrations were measured in plasma and in microdialysis perfusates from the underlying tissues. Iontophoretic application resulted in the highest plasma concentration of 3.4±0.5 ng/ml (SEM given) compared to 0.4 ng/ml (at the detection limit) with gel, whereas no differences were observed between tissue concentrations for the two application methods, both being very low, below or around the detection limit. Iontophoresis caused skin reactions in 25% of the participants. Iontophoresis of diclofenac as compared to traditional topical application was not superior in order to increase the NSAID concentration locally and appears to have a higher frequency of skin reactions.

Nonsteroidal antiinflammatory drugs (NSAIDs) and paracetamol for acute musculoskeletal injuries: physiotherapists' understanding of which is safer, more effective, and when to initiate treatment

Physiotherapists are primary care practitioners, and are often the first health professional to consult with patients presenting with acute sprains or strains, and such patients may ask for advice regarding medications. Paracetamol and nonsteroidal anti-inflammatory drugs (NSAIDs) are readily available without a prescription and are commonly used by patients. The aim of this study was to investigate New Zealand physiotherapists' knowledge regarding the comparative safety, effectiveness, and appropriate timing of paracetamol and NSAIDs for acute musculoskeletal sprains and strains. A questionnaire was mailed to all members of the New Zealand Society of Physiotherapists currently practicing in the field of musculoskeletal physiotherapy (n = 948). Of 278 respondents (29.3%), just over half (52%) thought that NSAIDs were more effective than paracetamol in the treatment of sprains and strains. Almost half (45%) believed that NSAIDs should be withheld because of the potential for interrupting the beneficial role of inflammation in healing and that NSAIDs could increase bleeding into the injured tissue. In contrast, the majority of respondents (81%) recognised that there was no need to withhold paracetamol in the initial postinjury period. Knowledge regarding safety, effectiveness, and risks of paracetamol and NSAIDs may assist physiotherapists to recommend appropriate management of acute musculoskeletal injuries, within regulatory boundaries.

Diclofenac epolamine plus heparin plaster versus diclofenac epolamine plaster in mild to moderate ankle sprain: a randomized, double-blind, parallel-group, placebo-controlled, multicentre, phase III trial

BACKGROUND

In general sports, ankle sprain is the most frequently reported ankle injury and can cause chronic lateral ankle pain and tenderness. Treatment with NSAIDs is preferred, and several topical NSAID formulations are now available, helping to avoid the systemic adverse events typically associated with oral preparations.

OBJECTIVE

To compare the efficacy and tolerability of a newly developed fixed-dose diclofenac epolamine (diclofenac hydroxyethylpyrrolidine, DHEP)/heparin plaster (Flectoparin® Tissugel) with that of a DHEP (Flector EP Tissugel®) or placebo plaster in the treatment of mild to moderate ankle sprain in adults.

METHODS

This was a randomized, double-blind, parallel-group, placebo-controlled, multicentre, phase III study conducted in the emergency medical centres of hospitals or private clinics in Europe. Outpatients aged 18-65 years who had suffered an acute ankle sprain (O'Donoghue grade I or II in severity, with external lateral ligament involvement) within the previous 48 hours and had peri-malleolar oedema were eligible for inclusion. A total of 430 patients were randomized to receive a DHEP/heparin 1.3%/5600 IU (n = 142), DHEP 1.3% (n = 146) or placebo (n = 142) plaster, applied once daily to the injured ankle for a total of 7 days. The primary endpoint was the mean change from baseline in pain on movement on day 3, as measured by a visual analogue scale (VAS).

RESULTS

The DHEP/heparin plaster was associated with a significantly (p = 0.002) greater mean reduction from baseline in pain on movement after 3 days of treatment than the DHEP plaster (-24.2 vs -18.8 mm VAS), with each active treatment providing significantly (p ≤ 0.005) greater pain relief than placebo (-13.7 mm VAS). Both DHEP/heparin and DHEP were also effective in relieving other measures of pain, with DHEP/heparin recipients experiencing significantly less daily pain while leaning on the injured limb than DHEP recipients (p < 0.001). In addition, oedema was reduced to a significantly greater extent with DHEP/heparin than with placebo (day 7 only; p = 0.012). The DHEP/heparin plaster and DHEP plaster were both well tolerated, with adverse event profiles similar to that of placebo. Local adverse events were infrequent and generally mild in severity and there were no systemic adverse effects.

CONCLUSION

The fixed-dose DHEP/heparin plaster is effective and has advantages over the DHEP plaster in relieving pain, and possibly also swelling, associated with mild to moderate acute ankle sprains with oedema in adults.

Topical diclofenac epolamine patch 1.3% for treatment of acute pain caused by soft tissue injury

Acute pain caused by musculoskeletal disorders is very common and has a significant negative impact on quality-of-life and societal costs. Many types of acute pain have been managed with traditional oral non-steroidal anti-inflammatory drugs (NSAIDs) and selective cyclooxygenase-2 inhibitors (coxibs). Data from prospective, randomised controlled clinical trials and postmarketing surveillance indicate that use of oral traditional NSAIDs and coxibs is associated with an elevated risk of developing gastrointestinal, renovascular and/or cardiovascular adverse events (AEs). Increasing awareness of the AEs associated with NSAID therapy, including coxibs, has led many physicians and patients to reconsider use of these drugs and look for alternative treatment options. Treatment with NSAIDs via the topical route of administration has been shown to provide clinically effective analgesia at the site of application while minimising systemic absorption. The anti-inflammatory and analgesic potency of the traditional oral NSAID diclofenac, along with its physicochemical properties, makes it well suited for topical delivery. Several topical formulations of diclofenac have been developed. A topical patch containing diclofenac epolamine 1.3% (DETP, FLECTOR(®) Patch), approved for use in Europe in 1993, has recently been approved for use in the United States and is indicated for the treatment of acute pain caused by minor strains, sprains and contusions. In this article, we review the available clinical trial data for this product in the treatment of pain caused by soft tissue injury.

Evaluation of glycofurol-based gel as a new vehicle for topical application of naproxen

In view of the good skin tolerability, glycofurol was used as a vehicle-based gel, and its effect in the topical penetration of Naproxen (NAP) was investigated. The aims of this study were to develop a suitable gel with bioadhesive property, spreadability, and viscosity for topical anti-inflammatory effect. Three gelling and adhesive agents were examined: Carbopol 974P, Gantrez AN 119, and polyvinylpyrollidone K30. Skin permeation rates and lag times of NAP were evaluated using the Franz-type diffusion cell in order to optimize the gel formulation. The permeation rate of NAP-based gel across the excised rat skin was investigated. A significant increase in permeability parameters such as steady-state flux (J(ss)), permeability coefficient (K(p)), and penetration index (PI) was observed in optimized formulation containing 2% Transcutol as an permeation enhancer. From skin irritation test, it was concluded that the optimized novel glycofurol-based gel formulation was safe to be used for topical drug delivery. The developed glycofurol-based gel appeared promising for dermal and transdermal delivery of naproxen and could be applicable with water-insoluble drugs, which would circumvent most of the problems associated with drug therapy.

Update on the use of topical NSAIDs for the treatment of soft tissue and musculoskeletal pain: a review of recent data and current treatment options

Topical nonsteroidal anti-inflammatory drugs (NSAIDs) have an emerging role in the treatment of certain types of acute pain. In addition to their convenience, efficacy, and safety, they are an attractive option, particularly when considering current concerns about the safety of traditional NSAIDs and cyclooxygenase-2 (COX-2) inhibitors (coxibs). Topical analgesics act largely within the peripheral nervous system. Studies have demonstrated that topical NSAIDs penetrate the skin and distribute to the target tissues underlying the application site. Because the pharmacologically effective dose is delivered at the site of pain, there is minimal systemic absorption and risk of related adverse events. Topical NSAIDs have been used for many years in Europe, with extensive post-marketing data available for some of the agents. Three topical NSAID formulations have recently been approved for use in the United States: the diclofenac epolamine topical patch 1.3% (DETP), diclofenac sodium 1% gel, and diclofenac sodium topical solution 1.5%. Topical NSAIDs provide a therapeutic option for treatment of acute, localized, soft tissue injuries or painful conditions in areas of the body that can be readily treated using the topical route of administration. This article reviews available data on the use of topical NSAID therapy.

Efficacy and safety profile of a topical methyl salicylate and menthol patch in adult patients with mild to moderate muscle strain: a randomized, double-blind, parallel-group, placebo-controlled, multicenter study

BACKGROUND

An occlusive patch formulation containing 10% methyl salicylate and 3% l-menthol was recently approved by the US Food and Drug Administration for the treatment of mild to moderate pain. Despite widespread use of counterirritants, including methyl salicylate and menthol, for topical pain relief, published efficacy and safety data regarding the use of the agents alone or in combination are limited.

OBJECTIVE

The goal of this study was to determine the efficacy and safety profile of a patch containing 10% methyl salicylate and 3% l-menthol compared with a placebo patch in adult patients with mild to moderate muscle strain.

METHODS

Eligible patients were men or women aged >or=18 years with a clinical diagnosis of mild to moderate muscle strain. Patients were randomly assigned to receive either 1 active patch or 1 placebo patch applied to the skin at the affected area (ie, shoulder, upper back, upper arm, neck, calf, thigh, forearm, abdomen). Pain intensity was assessed on a 100-mm visual analog scale while at rest and with movement for 12 hours after patch application. The primary efficacy end point was the summed pain intensity difference score through 8 hours (SPID8) with movement. Analyses included use of descriptive statistics and an ANOVA model. Safety data, including adverse events, and secondary efficacy end points were also evaluated.

RESULTS

A total of 208 patients (104 men, 104 women; age range, 18-78 years) were randomized to 1 of 2 study groups (105 in the active-patch group [mean age, 37.3 years], 103 in the placebo-patch group [mean age, 38.1 years]). The primary efficacy analysis (SPID8 with movement) indicated that patients receiving the active patch experienced significantly greater pain relief (approximately 40%) than those patients receiving a placebo patch (mean [SD], 182.6 [131.2] vs 130.1 [144.1]; P = 0.005). Analysis of the per-protocol population also found significantly more relief (P = 0.024) in the active-patch group (176.2 [131.4]; n = 92) versus the placebo-patch group (130.2 [144.0]; n = 96). Statistical analysis of secondary efficacy measures supported the primary end-point results. The number of patients experiencing any type of adverse event was comparable between study groups (active patch, 6.7% [7 events]; placebo patch, 5.8% [6 events]). No serious adverse events were reported during the study.

CONCLUSION

A single, 8-hour application of a patch containing methyl salicylate and l-menthol provided significant relief of pain associated with mild to moderate muscle strain in these adult patients compared with patients receiving a placebo patch.

Pathophysiology of TMD pain--basic mechanisms and their implications for pharmacotherapy

This article discusses the pathophysiology of temporomandibular disorders (TMD)-related pain and its treatment with analgesic drugs. Temporomandibular disorders are comprised of a group of conditions that result in temporomandibular joint pain (arthralgia, arthritis) and/or masticatory muscle pain (myofascial TMD). In at least some patients with TMD, a peripheral mechanism contributes to this pain. However, there is often a poor correlation between the severity of TMD-related pain complaints and evidence of definitive tissue pathology. This has led to the concept that pain in some patients with TMD may result from altered central nervous system pain processing and further that this altered pain processing may be attributable to specific genes that are heritable. Psychosocial stressors are also thought to contribute to the development of TMD-related pain, particularly masticatory muscle pain. Finally, substantially more women suffer from TMD than men. Although there are arguably multiple reasons for sex-related differences in the prevalence of TMD, one candidate for the increased occurrence of this disorder in women has been suggested to be the female sex hormone oestrogen. Analgesic drugs are an integral part of the primary treatment for TMD-related pain and dysfunction with more that 90% of treatment recommendations involving use of medications. The most commonly used agents include non-steroidal anti-inflammatory drugs, corticosteroids, muscle relaxants, anxiolytics, opiates and tricyclic antidepressants, however, evidence in support of the effectiveness of these drugs is lacking. Continued research into the pathophysiology of TMD-related pain and the effectiveness of analgesic treatments for this pain is required.

Recommendations of community pharmacists for the treatment of sprains and strains

Objective

To determine the recommendations that community pharmacists make when treating ankle sprains and strains, in particular regarding the use of non-steroidal anti-inflammatory drugs (NSAIDs). The current debate about this issue is whether to initiate NSAIDs immediately post-injury, or withhold for the first 48 hours to allow inflammation to occur. The opposing viewpoints are that ‘inflammation is a barrier to healing’ and that ‘inflammation is vital for healing’

Method

In August 2005, a structured questionnaire was mailed to 493 community pharmacies throughout New Zealand and addressed to the pharmacist. Questions covered the advice and interventions (both pharmacological and non-pharmacological) that would be given to a patient presenting with a strain or sprain, beliefs about different analgesics and their role in treatment, and information relating to their postgraduate qualifications and prevalence of sprains and strain seen in their pharmacy.

Key findings

The response rate was 46.5% (229), the mean number of sprains reported in a month was nine. Ninety-six per cent (219) of pharmacists recommended RICE (rest, ice, compression, elevation) as the mainstay of treatment in these types of injuries, and analgesics were recommended frequently, 89% (201). Almost half, 46% (104) of the pharmacists thought that NSAIDs should be withheld for 24–48 h post-injury, and almost half, 46% (104) did not; the remainder, 8% (17) were unsure.

Conclusion

Current evidence is moving away from using NSAIDs immediately post-injury to treat strains and sprains. While many pharmacists are aware of this, there are still others who are either unaware of this new research or who disagree. Most pharmacists were treating these injuries well, but pharmacists need to be aware of current recommendations to make sure that they follow ‘best practice’ and minimise further harm to their patients.

Percutaneous absorption of topically applied NSAIDS and other compounds: role of solute properties, skin physiology and delivery systems

Topical NSAIDS and related solutes are often applied to the skin to target tissues directly below the application site. We have used both biopsy and microdialysis techniques to show that most solutes penetrate below dermal capillaries into the subcutaneous and deeper tissues of both rats and human subjects. The selectivity of local penetration is time related, the concentrations in underlying tissues at longer times often being defined by recirculation from the systemic blood supply. Increased depths of penetration may be achieved by the use of vasoactive agents. Iontophoretic and other delivery systems appear to increase the efficiency of drug delivery through the stratum corneum and do not appear to greatly facilitate penetration into tissues below the dermis. Vehicle polarity and solute properties such as size can be used to advantage in delivering NSAIDs to deeper tissues.The pharmacokinetics of NSAIDs in the dermis and other tissues appears to be related to the absorption of solutes through the stratum corneum, binding of the NSAIDs to dermal and other tissues and clearance of NSAIDs from these tissues through either diffusion into deeper tissues or removal by the systemic blood supply. The latter is dependent on the blood flow to the tissues and protein binding of the NSAIDs in the blood. Absorption of NSAIDs and other solutes through the stratum corneum is defined by their inherent hydrogen bonding ability, lipophilicity and size as well as the interactions between the solute, vehicle and skin.The literature contains a number of examples of pharmacological efficacy after topical application which can now be better explained in terms of our recently gained understanding of the pharmacokinetics of NSAIDs after topical application. A complicating aspect in this interpretation is the variation in efficacy between the various models used to date.