The role of tramadol in pain management in Latin America: a report by the Change Pain Latin America Advisory Panel

A green impedimetric aptasensor for non-invasive and high-selective detection of tramadol validated by molecular dynamic simulation

Although the dosage controlling of tramadol (TRA) as a banned deadly drug in human biofluids is medicolegally important a biocompatible method for its high-selective detection with fewer false interferences has been scarcely reported. Herein, a new impedimetric aptasensor is introduced by utilizing the aptamer (Apt) sequence with high affinity to TRA for the first time to non-invasively measure it. An oriented nanolayer of Au nanoparticles (AuNPs) is easily formed on the surface by the electrodeposition technique to high-densely load the Apt and embed the novel aptasensing interface via a user-friendly methodology. The visual interaction of Apt with its target has been explored using molecular dynamic (MD) simulation to confirm how Apt traps TRA in its arm. The aptasensor measured TRA in a concentration range of 50 pM to 1.3 nM with a limit of detection (LOD) of 16.66 pM in buffer. It also rendered good accuracy and recovery for human salivary and urinary analysis. In addition, the greenness profile of the proposed methodology has been validated with two international common indexes. The developed aptasensor promises a reasonable capability for TRA monitoring in real clinical or street narcotic samples according to green analytical chemistry (GAC).

Tramadol use and public health consequences in Iran: a systematic review and meta-analysis

BACKGROUND AND AIMS

Misuse of tramadol, an opioid prescription analgesic, is known as a public health challenge globally. We aimed to systematically review studies on the prevalence of non-prescribed use, regular tramadol use and dependence, tramadol-induced poisoning and mortality in Iran.

METHODS

Consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, international (Medline, Scopus, Web of Science) and Persian (SID) databases were systematically searched up to June 2019. Other relevant data were collected through personal contacts and review of reference lists. Pooled estimates of prevalence of tramadol use in subgroups of males and females, percentage of tramadol poisoning among admitted poisoning cases, tramadol-associated seizures and mortality among tramadol poisonings and percentage of tramadol as a cause of death among fatal drug-poisoning records were estimated through a random-effects model.

RESULTS

A total of 84 records were included. Pooled estimates of last 12-month use of tramadol in the Iranian general population were 4.9% [95% confidence interval (CI) = 4.1-5.9] and 0.8% (95% CI = 0.2-1.8) among males and females, respectively. The estimates for last 12-month use among Iranian male and female university students were 4.8% (95% CI = 1.9-8.9) and 0.7% (95% CI = 0.3-1.1), respectively. Six heterogeneous reports indicated the existence of regular use of tramadol and dependence in Iran. Sixty-two studies provided data on tramadol-induced poisoning, seizures and mortality. The pooled estimate of the percentage of tramadol poisoning among all drug-poisoning patients was 13.1% (95% CI = 5.7-22.9). The overall estimates of seizures and mortality among tramadol-poisoning patients were 34.6% (95% CI = 29.6-39.8) and 0.7% (95% CI = 0.0-1.9), respectively. The pooled percentage of tramadol-related fatalities among drug-poisoned cases was 5.7% (95% CI = 0.5-15.4).

CONCLUSION

Despite control policies, tramadol use is as prevalent as the use of illicit opioids in Iran. Numerous cases of tramadol abuse, dependence, poisonings, seizures and hundreds of tramadol-related deaths have been reported in recent years.

Tramadol sensing in non-invasive biological fluids using a voltammetric electronic tongue and an electrochemical sensor based on biomimetic recognition

Tramadol (TRA) is a weak opioid analgesic, prescribed to relieve mild to moderately severe pain. However, side effects of TRA overdoses, including vomiting, depression, tachycardia, convulsions, morbidity and mortality are often reported. In this study, an electrochemical sensor based on molecularly imprinted conductive polymer was firstly developed for the quantitative and non-invasive detection of TRA. Secondly, a voltammetric electronic tongue (VE-Tongue) combined with chemometric methods was used for the qualitative analysis. The MIP sensor was constructed by self-assembling a poly-aniline layer coated with silver nanoparticles (PANI-AgNPs) on a screen-printed gold electrode (Au-SPE). Then, 2-amino-thiophenol was polymerised in the presence of TRA. The electronic device exhibits, under optimal conditions, responses proportional to TRA concentrations (0.01-100 µg/mL) with detection and quantification limits of 9.42 µg/mL and 28.55 µg/mL, respectively. Moreover, its selectivity was proven by insignificant interferences of substances (paracetamol and citric acid). Spiked saliva and urine samples were used for the sensor practical application with a significant recovery above 90% and standard deviations below 4.5%. Besides, urine samples' analyses using VE-Tongue and pattern recognition methods show good discrimination, classification, and prediction results with scores above 95%. Correspondingly, both electro-analytical devices could be viable for monitoring drugs in biological matrices.

Preclinical assessment of tramadol abuse potential: Effects of acute and repeated tramadol on intracranial self-stimulation in rats

BACKGROUND

Tramadol is a widely used analgesic that activates mu-opioid receptors (MOR) and inhibits serotonin and norepinephrine transporters. This mixed pharmacology may limit both its own abuse potential and its modulation of abuse potential of other MOR agonists.

AIMS

This study used an intracranial self-stimulation (ICSS) procedure to compare abuse-related effects produced by acute or repeated treatment with tramadol or morphine in rats. Abuse potential in ICSS procedures is indicated by a drug-induced increase (or 'facilitation') of ICSS responding.

METHODS

Adult male Sprague-Dawley rats were implanted with electrodes targeting the medial forebrain bundle and trained to respond on a lever for pulses of electrical brain stimulation. Tramadol effects were evaluated after acute administration (3.2-32 mg/kg) in the absence or presence of the opioid antagonist naltrexone, the CYP2D6 hepatic-enzyme inhibitor quinine or a combination of both. Additionally, both tramadol and morphine were also tested before and after repeated tramadol (32 mg/kg/day for six days) or repeated morphine (3.2 mg/kg/day for six days).

RESULTS

Acute tramadol produced primarily ICSS rate-decreasing effects that were antagonised by naltrexone but not by quinine or naltrexone + quinine. Tramadol also produced little or no ICSS facilitation after repeated tramadol or repeated morphine, and repeated tramadol did not enhance ICSS facilitation by morphine. By contrast, morphine-induced ICSS facilitation was enhanced by repeated morphine treatment.

CONCLUSIONS

These results suggest that tramadol has lower abuse potential than other abused MOR agonists and that repeated tramadol exposure produces relatively little enhancement of abuse potential of other MOR agonists.

Tramadol for management of fibromyalgia pain and symptoms: Systematic review

BACKGROUND

Fibromyalgia is a heterogeneous condition that appears to be associated with physiological and biochemical disturbances of pain modulation, and that consequently affects numerous other facets of life. Tramadol is currently being explored as an option to manage fibromyalgia pain and other symptoms because of its inhibitory activity of reuptake of neurotransmitters, but its safety and efficacy have not yet been established in these patients.

OBJECTIVE

To evaluate the effectiveness and safety of tramadol on the management of symptoms of the syndrome.

METHODS

We searched CENTRAL, MEDLINE, EMBASE, LILACS, Opengrey, ClinicalTrials.gov and WHO-ICTRP for randomised controlled trials analysing the association between tramadol used for fibromyalgia either single-agent or in combination with other drugs. Two reviewers independently extracted data and assessed risk of bias using the Cochrane risk-of-bias tool for all included studies. Quality of the evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

Four RCTs comprising 459 patients were included. Tramadol-either as a single-agent or in combination with an antidepressant or analgesic-had a positive effect on pain. Tramadol combined with analgesic showed improved quality of life over placebo as measured by the Fibromyalgia Impact Questionnaire at 91 days. However, this difference did not hold for tramadol as a single agent against placebo. The evidence in these articles was rated "low" using the GRADE approach. No serious adverse events were reported. No improvement in depression and quality of sleep were observed.

CONCLUSIONS

This systematic review found a dearth of clinical trials on tramadol in patients with fibromyalgia. Although the combination of monoamine and opioid mechanism of tramadol has shown positive effects for fibromyalgia, the available evidence is not sufficient to support or refute the use of tramadol in clinical practice for pain or symptom management. Protocol registration number in the PROSPERO database: CRD42017062139.

Sustainability of Palliative Care in a Rural Hospital in Tanzania: A Longitudinal and Prospective 4-Year Study

BACKGROUND

Palliative care has been developed in recent years in many sub-Saharan countries in Africa due to activities of African Association for Palliative Care. Palliative care units have been established also in most hospitals in Tanzania. Yet very little is known about their functions. Long-term studies about the sustainability of palliative care have not been carried out.

METHODS

The attitudes of 101 members of hospital staff and persons in charge of palliative care services of Ilembula District Designated Hospital (IDDH), Tanzania, were assessed using a modified and prevalidated questionnaire annually in 2014 to 2017. The inquiries were executed on randomly allocated days. Also, the patient and economy registries were analyzed. Additional qualitative data were obtained in personal interviews and during observational visits twice a year at the IDDH.

RESULTS

Ilembula District Designated Hospital has a true multiprofessional palliative care team, which provides services in the hospital, in the villages, and at homes. The activities are based on careful 5-year planning and budgeting. Up to 17 villages have been included in the services. Ninety-five percent of the patients were HIV infected. Short-acting morphine oral solution was the only available strong opioid. The hospital staff evaluated palliative care as good or excellent; 50% of the staff would need more support in the end-of-life care.

CONCLUSIONS

A sustainable palliative care service can be built in a Tanzanian rural hospital if an advanced planning and budgeting are made. In Tanzania, the biggest group of palliative care patients are still HIV-infected individuals. There is a lack of opioids in the country.

Tramadol: a valuable treatment for pain in Ghana and Nigeria

OBJECTIVE

Pain management is unsatisfactory worldwide, particularly in developing countries where access to opioids is restricted and cost is an issue. It is a major concern in West Africa and we therefore undertook a survey of pain experts to obtain a better understanding of the problems in the region.

METHODS

Medical practitioners involved in pain management, identified via professional networks, were interviewed to share their experience in treating moderate-to-severe pain in West Africa. The questionnaire was based on an existing version modified to meet African conditions. Additionally, informal focus group meetings with palliative care physicians and pharmacists were conducted.

RESULTS

A total of 11 questionnaires were returned. All respondents were physicians who reported availability of opioids in their clinics, but access to morphine was challenging and not possible in some rural settings. Obligatory maintenance of detailed records was considered a burden. The main concern raised was the risk of misuse/addiction. Seven of 11 respondents reported that they would use tramadol as an alternative to strong opioids if required and, interestingly, 9 of 11 considered it to be an essential medicine. Based on personal experience, the respondents noted that some properties of tramadol make it a key pain treatment option in West Africa (strong/fast-acting, better tolerated than NSAIDs, less addictive than other opioids and relatively inexpensive).

CONCLUSIONS

Most stakeholders who completed the survey indicated that tramadol was essential to provide optimal pain management in the absence of access to strong opioids.

A Systematic Review of Laboratory Evidence for the Abuse Potential of Tramadol in Humans

Background: Tramadol is an opioid-analgesic that has shown epidemiological evidence of abuse. This review evaluates the evidence for tramadol abuse potential in humans. Methods: A systematic literature search for human abuse liability examinations of tramadol was conducted in September 2018 and yielded 13 total studies. Studies were all within-subject, double-blind, placebo-controlled human laboratory comparisons of tramadol to opioid comparators. Results are organized based upon the route of tramadol administration (oral, parenteral) and the participant population (persons with and without current opioid physical dependence). Outcomes were categorized into self-report ratings of positive and negative effects, observer-ratings of effects, time course of effects, likelihood tramadol was identified as an opioid, and tramadol self-administration. Results: Results indicated the relative abuse potential of tramadol was lower than the opioids to which it was compared. Tramadol produced highest positive effect ratings when administered orally to persons with no opioid physical dependence. Relative to other opioids, it produced substantial negative ratings, generally demonstrated a slower onset of effects, and was less likely to be identified by participants as an opioid, though it did produce a higher rate of self-administration relative to other opioids in the one study reporting that outcome. Results suggest that the abuse potential of tramadol is highest when it is administered orally to non-dependent individuals, and that it likely decreases as the dose increased and when it was administered parentally or to persons with opioid physical dependence. Conclusion: Taken together, individuals may be less likely than with other opioids to escalate tramadol doses, transition from oral to parenteral routes of administration, or continue using tramadol once opioid physical dependence develops. In that way, the human abuse potential of tramadol appears to be different from and lower than other opioid analgesic medications.

Comparison of different sufentanil-tramadol combinations for pain relief within the first 24 hours after cesarean section: a retrospective study

Introduction

Postcesarean section pain management is important for both the mother and the newborn. This study compared the analgesic effects and incidence of adverse events associated with intravenous patient-controlled analgesia (iv-PCA), using different sufentanil–tramadol combinations for postoperative pain control.

Methods

Parturients (n=5,794) who had been scheduled for cesarean section under neuraxial anesthesia and had received iv-PCA between September 2013 and March 2017 were retrospectively analyzed. These patients were assigned to three groups, based on different sufentanil–tramadol combinations: ST1 (n=1,347), ST2 (n=2,401), and ST3 (n=2,046). The analgesic efficacy, total drug consumption, and incidence of adverse effects within 24 hours after surgery were compared among the three groups.

Results

The ST3 group had lower visual analog scale pain scores at rest and with movement at all time points during the first 24 hours postoperatively than the other two groups (P<0.01, Bonferroni corrected). The sufentanil dosage administered to the ST3 group was lower, and the tramadol dosage was higher than those administered to the other groups within 24 hours after surgery (P<0.01, Bonferroni corrected). Moreover, all parturients scored 2 points on the Ramsay sedation scale. Adverse reactions such as pruritus and respiratory depression were not observed in any group. No significant differences were noted in the incidence of nausea/vomiting, abdominal distension, and dizziness among the three groups (P>0.05).

Conclusion

The visual analog scale scores for postoperative pain decreased as the concentrations of sufentanil and tramadol administered in iv-PCA moderately increased over 24 hours after surgery. This analgesic strategy resulted in a significant reduction in the total sufentanil requirement without increasing the incidence of adverse effects.