Parallel intraindividual evaluation of the vasoconstrictory action and the anti-allergic activity of topical corticosteroids

Comparison of dexmedetomidine and dexamethasone as adjuvants to the ultrasound-guided interscalene nerve block in arthroscopic shoulder surgery: a systematic review and Bayesian network meta-analysis of randomized controlled trials

Introduction

Interscalene block (ISB) is widely regarded as the gold standard treatment for acute pain following arthroscopic shoulder surgery. However, a single injection of a local anesthetic for ISB may not offer sufficient analgesia. Various adjuvants have been demonstrated to prolong the analgesic duration of the block. Hence, this study aimed to assess the relative efficacy of dexamethasone and dexmedetomidine as adjuncts to prolong the analgesic duration for a single- shot ISB.

Methods

The efficacy of adjuvants was compared using a network meta-analysis. The methodological quality of the included studies was evaluated using the Cochrane bias risk assessment tool. A comprehensive search of the PubMed, Cochrane, Web of Science, and Embase databases was conducted with a search deadline of March 1, 2023. Various adjuvant prevention randomized controlled trials have been conducted in patients undergoing interscalene brachial plexus block for shoulder arthroscopic surgery.

Results

Twenty-five studies enrolling a total of 2,194 patients reported duration of analgesia. Combined dexmedetomidine and dexamethasone (MD = 22.13, 95% CI 16.67, 27.58), dexamethasone administered perineurally (MD = 9.94, 95% CI 7.71, 12.17), high-dose intravenous dexamethasone (MD = 7.47, 95% CI 4.41, 10.53), dexmedetomidine administered perineurally (MD = 6.82, 95% CI 3.43, 10.20), and low-dose intravenous dexamethasone (MD = 6.72, 95% CI 3.74, 9.70) provided significantly longer analgesic effects compared with the control group.

Discussion

The combination of intravenous dexamethasone and dexmedetomidine provided the greatest effect in terms of prolonged analgesia, reduced opioid doses, and lower pain scores. Furthermore, peripheral dexamethasone in prolonging the analgesic duration and lowering opioid usage was better than the other adjuvants when used a single medication. All therapies significantly prolonged the analgesic duration and reduced the opioid dose of a single-shot ISB in shoulder arthroscopy compared with the placebo.

Addition of 2 mg dexamethasone to improve the anesthetic efficacy of 2% lidocaine with 1:80,000 epinephrine administered for inferior alveolar nerve block to patients with symptomatic irreversible pulpitis in the mandibular molars: a randomized double-blind clinical trial

Introduction

This clinical trial aimed to evaluate the anesthetic effect of the addition of 2 mg (4 mg/ml) of dexamethasone to 2% lidocaine (plain or with 1:80,000 epinephrine). The solutions were injected for a primary inferior alveolar nerve block (IANB) to provide mandibular anesthesia for the endodontic treatment of mandibular molars with symptomatic irreversible pulpitis.

Methods

In a double-blinded setup, 124 patients randomly received either of the following injections: 2% lidocaine with 1:80,000 epinephrine, 2% lidocaine with 1:80,000 epinephrine mixed with 2 mg dexamethasone, or plain 2% lidocaine mixed with 2 mg dexamethasone, which were injected as a primary IANB. Ten minutes after injection, patients with profound lip numbness underwent electric and thermal pulp sensibility tests. Patients who responded positively to the tests were categorized as "failed" anesthesia and received supplemental anesthesia. The remaining patients underwent endodontic treatment using a rubber dam. Anesthetic success was defined as "no pain or faint/weak/mild pain" during endodontic access preparation and instrumentation (HP visual analog scale score < 55 mm). The effect of the anesthetic solutions on the maximum change in heart rate was also evaluated. The Pearson chi-square test at 5% and 1% significance was used to analyze anesthetic success rates.

Results

The 2% lidocaine with 1:80,000 epinephrine, 2% lidocaine with 1:80,000 epinephrine mixed with 2 mg dexamethasone, and plain 2% lidocaine mixed with 2 mg dexamethasone groups had anesthetic success rates of 34%, 59%, and 29%, respectively. The addition of dexamethasone resulted in significantly better results (P < 0.001, χ² = 9.07, df = 2).

Conclusions

The addition of dexamethasone to 2% lidocaine with epinephrine, administered as an IANB, can improve the anesthetic success rates during the endodontic management of symptomatic mandibular molars with irreversible pulpitis.

Analgesic Effect of the Topical Use of Dexamethasone in Ultrasound-Guided Axillary Brachial Plexus Blockade: A Prospective, Randomized, Double-Blind, Placebo-Controlled Study

Introduction

Increasing the duration of regional anesthesia in orthopedic surgery is of vital importance, as it prolongs postoperative analgesia, allowing faster rehabilitation of patients. Dexamethasone has been found to extend the block duration in animal and human studies. The aim of this study is the assessment of the effect of the addition of dexamethasone to ropivacaine on the onset and duration of axillary brachial plexus block, along with the intensity of postoperative pain.

Methods

Forty patients undergoing below-elbow surgery under ultrasound-guided axillary brachial plexus block were randomly allocated to receive either 30 mL ropivacaine 0.75% with 2 mL of saline (Group A, n = 20) or 30 mL ropivacaine 0.75% with 2 mL of dexamethasone (4 mg) (Group B, n = 20). Sensory and motor blockade were assessed, with the use of the pinprick test and the modified Bromage scale, at five, 10, 15, and 20 min after the block. The duration of analgesia, intensity of postoperative pain, postoperative opioid consumption, overall satisfaction, and perioperative complications were compared between the two groups.

Results

We found no difference at the mean onset time of the sensory and motor block between the two groups. The mean duration of postoperative analgesia was three hours higher in the dexamethasone group (15.85 ± 4.82 versus 11.75 ± 6.81, p-value = 0.035). Pain intensity was lower in the dexamethasone group, at six and 12 hours after surgery (3.45 ± 1.79 versus 4.65 ± 1.79, p-value = 0.040). Postoperative opioid consumption, patient overall satisfaction, and perioperative complications were not significantly different between groups.

Conclusions

Dexamethasone prolongs the duration of ropivacaine in an axillary brachial plexus block and decreases postoperative pain in patients subjected to below-elbow surgery.

Anti-inflammatory potency testing of topical corticosteroids and calcineurin inhibitors in human volunteers sensitized to diphenylcyclopropenone

AIMS

To quantify the anti-inflammatory potency of topical corticosteroids and topical calcineurin inhibitors by measuring the contact allergic response to a diphenylcyclopropenone (DPCP) challenge in de novo sensitized human volunteers.

METHODS

Two randomized, double-blind, vehicle-controlled studies were performed encompassing 76 volunteers: 29 in the first and 47 in the second study. Topical drugs were applied pre- and/or post-treatment in block designs. The compounds were tested simultaneously under occluded patch tests covering DPCP-induced dermatitis. Inhibitory responses were assessed by visual scoring and measurements of the oedema thickness with ultrasound.

RESULTS

When applied both before and after the DPCP challenge, significant anti-inflammatory effects were seen in descending order for tacrolimus 0.1% ointment, clobetasol propionate ointment, betamethasone valerate ointment and hydrocortisone butyrate ointment, while pimecrolimus cream, hydrocortisone ointment and vehicles had no significant effect. Only tacrolimus ointment (P < 0.01) demonstrated a consistent significant pre-treatment inhibitory effect compared with an untreated DPCP control.

CONCLUSIONS

This human testing method in which the inflammation of experimentally induced allergic patch test reactions is quantified by objective measurement allows an analysis of the anti-inflammatory potency of not only topical corticosteroids, but also of drugs that have no effect on vasoconstriction. The method allowed comparison of the potencies of four topical corticosteroids and two calcineurin inhibitors.

Effect of Dexamethasone on Characteristics of Supraclavicular Nerve Block with Bupivacaine and Ropivacaine: A Prospective, Double-blind, Randomized Control Trial

Background:

Dexamethasone as an adjuvant to bupivacaine and ropivacaine for supraclavicular brachial plexus (SCBP) block prolongs motor and sensory blockade. However, comparison of effect of dexamethasone (8 mg) when added to these two local anesthetics has not been well studied. This study was conducted to compare analgesic efficacy of dexamethasone as adjuvant to bupivacaine and ropivacaine in SCBP block.

Subjects and Methods:

Nerve stimulator-guided SCBP block was given to 120 patients, randomly assigned to one of four groups: (n = 30 in each group) Group B, BD, R, and RD received 30 ml (0.5%) bupivacaine + 2 ml saline, 30 ml (0.5%) bupivacaine + dexamethasone 8 mg, 30 ml (0.5%) ropivacaine + 2 ml saline, and 30 ml (0.5%) ropivacaine + dexamethasone 8 mg, respectively. Time for request of the first rescue analgesic, 24-h analgesic consumption, and different block characteristics were assessed. Student's t-test, Chi-square test, ANOVA were used for statistical analysis.

Results:

Dexamethasone significantly prolonged time for request of the first rescue analgesic of both ropivacaine (1211.83 ± 32.86 vs. 283.17 ± 7.71 min){ p R, RD < 0.001} and bupivacaine (1205.17 ± 34.32 vs. 364.67 ± 16.50 min) {p B, BD < 0.001}. 24-h requirement for rescue analgesics was more in Groups B and R when compared to Groups BD and RD. The increase in duration of analgesia was more when Groups R and RD (928.66 min) were compared than Groups B and BD (840.5 min). Similar results were seen with onset times and duration of sensory and motor block.

Conclusion:

The addition of dexamethasone to bupivacaine and ropivacaine in SCBP block prolonged time for first rescue analgesia and reduced the requirement of rescue analgesics with faster onset and prolonged duration of sensory and motor block, with the effect being stronger with ropivacaine.

Increased bioavailability of hydrocortisone dissolved in a cream base

BACKGROUND/OBJECTIVES

The aim of this study was to compare vasoconstrictor activity and, by inference, the clinical anti-inflammatory effectiveness of hydrocortisone in two different formulations: 1% dissolved hydrocortisone cream and 1% dispersed hydrocortisone cream. Moisturising capacity and safety were also determined.

METHODS

Both topical preparations were applied without occlusion on forearms twice daily for 5 days. An assessment of vasoconstriction was performed in a double-blinded manner pretreatment and then thrice daily for 6 days and once 7 days post-application, using an objective rating scale. For the dissolved preparation only, moisturising capacity was determined by measurement of transepidermal water loss (TEWL) at 0, 2, 4, 6 and 24 h, and also by the measurement of water content at 0 and 24 h. Safety was assessed by repeat insult patch tests (RIPT).

RESULTS

In all, 10 volunteers completed the vasoconstrictor and moisturising studies, while 52 completed the RIPT. For 1% dissolved hydrocortisone cream and 1% dispersed hydrocortisone cream, respectively, areas under the blanching curves were 1240 and 295; total scores were 129.0 and 31.5; summed % total possible scores were 161.3 and 39.4; Tm/10 mean values were 3.47 and 1.64. The 1% dissolved hydrocortisone cream was found to be statistically more potent than the 1% dispersed hydrocortisone cream. Furthermore, the 1% dissolved hydrocortisone cream was found to be moisturising compared to no treatment. No adverse events were observed.

CONCLUSIONS

A cream containing 1% dissolved hydrocortisone exhibits greater vasoconstrictor activity than a cream containing 1% dispersed hydrocortisone.

Effect of adding dexamethasone to bupivacaine on transversus abdominis plane block for abdominal hysterectomy: A prospective randomized controlled trial

PURPOSE

Different adjuvants have been used to improve the quality and increase the duration of local anesthetics during various nerve block techniques. The current study was aimed to evaluate the effect of adding dexamethasone to bupivacaine on the quality and duration of transversus abdominis plane (TAP) block.

METHODS

Sixty adult patients undergoing elective open abdominal hysterectomy were randomly allocated to receive TAP block using 20 mL of bupivacaine hydrochloride 0.25% + 2 mL saline 0.9% (control group, n=30) or 20 mL of bupivacaine hydrochloride 0.25% + 2 mL dexamethasone "8 mg" (dexamethasone group, n=30). The primary outcome was postoperative pain, as evaluated by visual analog scale (VAS) for pain scoring at 1, 2, 4, 12, 24 and 48 h postoperatively, whereas the secondary outcomes were time to first analgesia (TFA), morphine consumption and the occurrence of nausea, vomiting or somnolence.

RESULTS

The pain VAS score was significantly lower at the postoperative 2 h (4.9 vs. 28.1, P=0.01), 4 h (12.2 vs. 31.1, P=0.01) and 12 h (15.7 vs. 25.4, P=0.02). Furthermore, TFA was significantly longer in the dexamethasone group (459.8 vs. 325.4 min, P=0.002), with lesser morphine requirements in the postoperative 48 h (4.9 vs. 21.2 mg, P=0.003) and lower incidence of nausea and vomiting (6 vs. 14, P=0.03). No complications attributed to the block were recorded.

CONCLUSION

Addition of dexamethasone to bupivacaine in TAP block prolonged the duration of the block and decreased the incidence of nausea and vomiting.

Addition of intrathecal Dexamethasone to Bupivacaine for spinal anesthesia in orthopedic surgery

OBJECTIVES

Spinal anesthesia has the advantage that profound nerve block can be produced in a large part of the body by the relatively simple injection of a small amount of local anesthetic. Intrathecal local anesthetics have limited duration. Different additives have been used to prolong spinal anesthesia. The effect of corticosteroids in prolonging the analgesic effects of local anesthetics in peripheral nerves is well documented. The purpose of this investigation was to determine whether the addition of dexamethasone to intrathecal bupivacaine would prolong the duration of sensory analgesia or not.

METHODS

We conducted a randomized, prospective, double-blind, case-control, clinical trial. A total of 50 patients were scheduled for orthopedic surgery under spinal anesthesia. The patients were randomly allocated to receive 15 mg hyperbaric bupivacaine 0.5% with 2 cc normal saline (control group) or 15 mg hyperbaric bupivacaine 0.5% plus 8 mg dexamethasone (case group) intrathecally. The patients were evaluated for quality, quantity, and duration of block; blood pressure, heart rate, nausea, and vomiting or other complications.

RESULTS

There were no signification differences in demographic data, sensory level, and onset time of the sensory block between two groups. Sensory block duration in the case group was 119±10.69 minutes and in the control group was 89.44±8.37 minutes which was significantly higher in the case group (P<0.001). The duration of analgesia was 401.92±72.44 minutes in the case group; whereas it was 202±43.67 minutes in the control group (P<0.001). The frequency of complications was not different between two groups.

CONCLUSION

This study has shown that the addition of intrathecal dexamethasone to bupivacaine significantly improved the duration of sensory block in spinal anesthesia without any changes in onset time and complications.

Addition of intrathecal Dexamethasone to Bupivacaine for spinal anesthesia in orthopedic surgery

Objectives:

Spinal anesthesia has the advantage that profound nerve block can be produced in a large part of the body by the relatively simple injection of a small amount of local anesthetic. Intrathecal local anesthetics have limited duration. Different additives have been used to prolong spinal anesthesia. The effect of corticosteroids in prolonging the analgesic effects of local anesthetics in peripheral nerves is well documented. The purpose of this investigation was to determine whether the addition of dexamethasone to intrathecal bupivacaine would prolong the duration of sensory analgesia or not.

Methods:

We conducted a randomized, prospective, double-blind, case-control, clinical trial. A total of 50 patients were scheduled for orthopedic surgery under spinal anesthesia. The patients were randomly allocated to receive 15 mg hyperbaric bupivacaine 0.5% with 2 cc normal saline (control group) or 15 mg hyperbaric bupivacaine 0.5% plus 8 mg dexamethasone (case group) intrathecally. The patients were evaluated for quality, quantity, and duration of block; blood pressure, heart rate, nausea, and vomiting or other complications.

Results:

There were no signification differences in demographic data, sensory level, and onset time of the sensory block between two groups. Sensory block duration in the case group was 119±10.69 minutes and in the control group was 89.44±8.37 minutes which was significantly higher in the case group (P<0.001). The duration of analgesia was 401.92±72.44 minutes in the case group; whereas it was 202±43.67 minutes in the control group (P<0.001). The frequency of complications was not different between two groups.

Conclusion:

This study has shown that the addition of intrathecal dexamethasone to bupivacaine significantly improved the duration of sensory block in spinal anesthesia without any changes in onset time and complications.

Eumovate (clobetasone butyrate) 0.05% cream with its moisturizing emollient base has better healing properties than hydrocortisone 1% cream: a study in nickel-induced contact dermatitis

BACKGROUND

The emollient base of a topical corticosteroid, through its moisturizing properties, can be a useful treatment adjunct.

OBJECTIVE

To compare the healing properties of Eumovate trade mark (clobetasone butyrate) 0.05% cream with its emollient base, hydrocortisone 1% cream and with no treatment.

METHODS

A single-centre, double-blind, intra-individual, comparative study that involved 18 volunteers with nickel-induced contact dermatitis. Following a positive patch test to nickel, sub-therapeutic amounts (10 micro l = 3 mg cm(-2)) of each of the treatments were applied twice daily for seven days to each of the four test sites.

RESULTS

In terms of the primary endpoint, a physician's global assessment after 7 days of treatment, clobetasone butyrate (CB) 0.05% cream showed a significantly better response than hydrocortisone (HC) 1% cream (78% vs 39%, difference -0.4, 95% CI -0.7 to -0.1; p = 0.046) or no treatment (78% vs 28%, difference -0.5, 95% CI -0.9 to -0.1; p = 0.016). CB 0.05% cream also showed a better response than its emollient base (78% vs 56%), though statistical significance was not achieved. In terms of moisturizing effects, there was no difference in transepidermal water loss (TEWL) between CB 0.05% cream and its emollient base. CB 0.05% cream treated sites did, however, have significantly lower values (i.e. were more moisturized) than untreated sites (difference -8.5, 95% CI -12.0 to -4.86; p < 0.001) or HC 1% treated sites (difference -7.1, 95% CI -11.0 to -3.4; p < 0.001). In terms of skin blanching activity, as expected the steroid-based creams achieved lower colorimetric values than the emollient base cream.

CONCLUSIONS

These results from experimentally induced skin inflammation indicate that CB 0.05% (as Eumovate 0.05% cream) has both more effective anti-inflammatory activity and better moisturizing properties than hydrocortisone 1% cream and that these effects are in part due to its efficient emollient base.

Activity of different desoximetasone preparations compared to other topical corticosteroids in the vasoconstriction assay

INTRODUCTION

We report on a double-blind, vehicle-controlled, single-center confirmatory study with random assignment. The purpose of the study was to investigate the topical bioavailability of different topical corticosteroid formulations in healthy human beings focussing on desoximetasone (DM).

MATERIALS AND METHODS

Two DM 0.25% formulations [ointment (DM-o) and fatty ointment (DM-fo, water-free); class III corticosteroids], the corresponding active ingredient-free vehicles and three comparators of different strength [clobetasol propionate 0.05% (CP 0.05%), fatty ointment, class IV; hydrocortisone (HC) 1%, fatty ointment, class I, and betamethasone (BM) 0.05%, fatty ointment, class III] were tested using the vasoconstriction assay. The degree of vasoconstriction (blanching) in the treatment field was compared to the one found in untreated control fields using chromametric measurements and clinical assessment.

RESULTS/CONCLUSION

DM-o 0.25%, DM-fo 0.25% and BM 0.05% showed similar vasoconstrictive potential, i.e., clear blanching. In fact, both DM preparations were proven to be noninferior to BM 0.05%, while CP 0.05% was found a little less active. HC 1.0% and the DM vehicles showed no clear-cut vasoconstrictive effect. No adverse events related to the study medications were observed. Good topical bioavailability of both DM formulations was detected by chromametric measurement and clinical assessment.

Onset of Action of Ciclesonide Once Daily in the Treatment of Seasonal Allergic Rhinitis

Ciclesonide is an intranasal corticosteroid approved for the treatment of allergic rhinitis. We conducted a randomized, double-blind, parallel-group, placebo-controlled study to evaluate the time to onset of action of ciclesonide 200 μg once daily in 502 adults with seasonal allergic rhinitis of at least 2 years’ duration. To trigger immunologic priming, patients underwent between one and five priming sessions with exposure to 3,500 grains/m3 (±500) of ragweed pollen in an environmental exposure chamber. The criteria for a successful priming session was a patient-assessed instantaneous total nasal symptom score of at least 6 (of a possible 12) and a nasal congestion or rhinorrhea score of at least 2 (of a possible 3) 90 minutes after allergen exposure during at least two consecutive priming sessions. Patients were then randomly assigned to receive either a single dose of ciclesonide 200 μg (n = 251) or placebo (n = 251) administered intranasally. The difference in the change from baseline total nasal symptom scores in the two groups was assessed hourly for 12 hours after administration. Onset of action was determined to have taken place the first time that the effects of ciclesonide, as reflected in the total nasal symptom score, were significantly greater than those of placebo at a particular hourly assessment, provided that the subsequent hourly assessment also showed a statistically significant difference. The onset of action of ciclesonide occurred within 1 hour of administration (p = 0.01 vs. placebo), and the significant difference in total nasal symptom scores between ciclesonide and placebo was maintained through post-treatment hour 12 (p ≤ 0.018).

Dexamethasone Added to Lidocaine Prolongs Axillary Brachial Plexus Blockade

Different additives have been used to prolong regional blockade. We designed a prospective, randomized, double-blind study to evaluate the effect of dexamethasone added to lidocaine on the onset and duration of axillary brachial plexus block. Sixty patients scheduled for elective hand and forearm surgery under axillary brachial plexus block were randomly allocated to receive either 34 mL lidocaine 1.5% with 2 mL of isotonic saline chloride (control group, n = 30) or 34 mL lidocaine 1.5% with 2 mL of dexamethasone (8 mg) (dexamethasone group, n = 30). Neither epinephrine nor bicarbonate was added to the treatment mixture. We used a nerve stimulator and multiple stimulations technique in all of the patients. After performance of the block, sensory and motor blockade of radial, median, musculocutaneous, and ulnar nerves were recorded at 5, 15, and 30 min. The onset time of the sensory and motor blockade was defined as the time between last injection and the total abolition of the pinprick response and complete paralysis. The duration of sensory and motor blocks were considered as the time interval between the administration of the local anesthetic and the first postoperative pain and complete recovery of motor functions. Sixteen patients were excluded because of unsuccessful blockade. The duration of surgery and the onset times of sensory and motor block were similar in the two groups. The duration of sensory (242 +/- 76 versus 98 +/- 33 min) and motor (310 +/- 81 versus 130 +/- 31 min) blockade were significantly longer in the dexamethasone than in the control group (P < 0.01). We conclude that the addition of dexamethasone to lidocaine 1.5% solution in axillary brachial plexus block prolongs the duration of sensory and motor blockade.

Eumovate (clobetasone butyrate 0.05%) cream: a review of clinical efficacy and safety

Topical steroid creams and ointments have been available as over-the-counter (OTC) medications for the self treatment of acute dermatitis and other steroid responsive skin disorders for more than ten years. Despite earlier fears, widespread availability and use of these creams is not associated with clinically significant adverse effects. In dermatological practice, hydrocortisone 1% remains the mainstay of treatment for facial eczema, but it is often not effective in eczema affecting other body areas. Eumovate(TM) (clobetasone butyrate 0.05%) cream has recently been made available as a pharmacy medication for the short-term management of acute eczema and allergic dermatitis by adults and children aged 10 or older, based on evidence derived from clinical trials involving over 3500 patients. This review summarises the key efficacy and safety data derived from 29 clinical trials and the post-licensing pharmacovigilance safety information, which supported the reclassification of this product for OTC use. These data show clobetasone butyrate 0.05% is more effective than 1.0% hydrocortisone in the treatment of eczema and more effective than flurandrenolone 0.0125% (p=0.01%) and a potent topical steroid hydrocortisone butyrate (p<0.05), in the treatment of psoriasis. A review of the effect of topical steroids on skin thickness concluded that, following short term application, there was no clinically significant difference between hydrocortisone 1.0% and clobetasone butyrate 0.05% in terms of potential for skin thinning. Similarly, even under extreme conditions, clobetasone butyrate 0.05% has negligible systemic absorption and has almost no effect on HPA axis function.

Increased beclomethasone-induced vasoconstriction in women with posttraumatic stress disorder

It has been hypothesized that patients with posttraumatic stress disorder (PTSD) show increased glucocorticoid sensitivity. The study tested beclomethasone-induced vasoconstriction (BIV), a measure of peripheral glucocorticoid sensitivity, in women with PTSD. A case-control design was employed in 33 PTSD patients and 33 healthy controls. BIV was tested using beclomethasone dipropionate (1-100 micro g/ml). Vasoconstriction was assessed after 15-18 h. Waking and afternoon salivary cortisol concentrations were measured. BIV ratings were significantly increased in PTSD at beclomethasone concentrations from 10-100 micro g/ml. Salivary cortisol concentrations did not differ between groups or correlate with BIV. Preliminary evidence has been found for increased peripheral glucocorticoid sensitivity in PTSD. Further study is required to replicate this finding and assess its relationship to the pathophysiology of the disorder.

Analysis of chromameter results obtained from corticosteroid-induced skin blanching assay: comparison of visual and chromameter data

In a Guidance document, the American FDA recommends the use of a Minolta chromameter rather than the human eye for the quantitative assessment of the pharmacodynamic blanching response produced by topical application of corticosteroids. The purpose of this study was to compare the appropriateness of the human eye and two models of chromameter for the estimation of skin blanching, in terms of the quality of the data generated by each method. The corticosteroid-induced skin blanching from four different betamethasone 17-valerate cream formulations was compared in a typical human skin blanching trial. The optimized assay methodology routinely practised in our laboratories was utilized. The blanching responses were assessed visually by three trained, independent observers and recorded by two chromameters (Minolta model CR-200 and model CR-300). The topical availability of the four creams was determined using visual scoring and chromameter measurements. All data were manipulated in such a manner as to produce a blanching response versus time profile from which AUBC analysis could be performed. Good correlation was observed between the visual assessments made by three independent observers. In contrast, moderate correlation was determined between visual, CR-200 and CR-300 measurements. Surprisingly, no direct linear relationship between the AUBCs produced by the two chromameters was observed indicating that the quality of the data obtained from the two instruments may not be equal. This investigation also indicated that the use of the chromameter is not completely objective. Visual scoring and chromameter measurement produce data sets that differ in quality. Each procedure needs to be validated and investigators have to be trained for both visual assessment and the operation of the chromameter, particularly with regard to the manipulation of the measuring head of the instrument.

In vitro testing of tensides employing monolayer cultures: a comparison with results of patch tests on human volunteers

Evaluation of the irritant potential of new products or ingredients prior to human testing is generally performed in vivo on animals. However, according to the 6th amendment and following updates of the European Community directive on cosmetic products (93/35/EEC), animal testing will be banned when suitable substitutes will be available. To know whether in vitro tests for assessment of skin irritancy provide results approaching human conditions, comparisons have to be made between data deriving from in vitro tests and skin response in humans. The aim of our study was to assess the validity of the monolayer culture system of normal human keratinocytes as a model for the evaluation of the irritant effects of detergents, by comparing in vitro cell culture data to in vivo acute skin irritancy effects of cocamidopropyl betaine (CAPB), an amphoteric compound, Tween 20 (TW20) (polysorbate 20) and Tween 80 (TW80) (polysorbate 80), representing nonionic compounds, applied to the skin of 24 healthy volunteers at a concentration similar to that employed in commercial products. As parameters for cytotoxicity, cell proliferation, cell membrane integrity and cell metabolism were assessed by cell counts, thymidine incorporation, MTT conversion, and Neutral Red uptake. In order to increase the sensitivity of the in vivo evaluation, bioengineering methods for assessment of the effects of test products on the skin were employed. Whereas all 4 in vitro methods ranked the tensides according to their toxicity in the following order: CAPB>SLS>TW20>TW80, both in vivo methods agreed in identifying SLS as the most irritating substance. Moreover, as compared with the irritation potential on human skin, all 4 in vitro tests overestimated the toxicity of CAPB. This suggests that the keratinocyte monolayer cell culture technique cannot directly replace in vivo methods, and that data obtained by this method should be interpreted cautiously.