Use of the French healthcare insurance database to estimate the prevalence of exposure to potential drug-drug interactions.

PURPOSE: Drug-drug interactions (DDIs) require monitoring in an aging population with increasing polypharmacy exposure. We aimed to estimate the prevalence of exposure to potential DDIs using the French healthcare insurance system database, for six DDIs with various clinical relevance: angiotensin II receptor blockers or angiotensin-converting enzyme inhibitors and nonsteroidal anti-inflammatory drugs (ARBs-ACEIs + NSAIDs), antiplatelet agents and NSAIDs (AAP + NSAIDs), serotonergic drugs and tramadol (SD + T), statins and macrolides (S + M), oral anticoagulant and NSAIDs (OAC + NSAIDs), and colchicine and macrolides (C + M). METHODS: We used exhaustive healthcare data from a 1/97th random sample of the population covered by the French health insurance system (EGB) between 2006 and 2016. Exposure to a DDI was defined as overlapping exposure to two interacting drugs. The prevalence of exposure was estimated by year. RESULTS: Prevalence of exposure in 2016 was estimated at 3.7% for ARBs-ACEIs + NSAIDs, 1.5% for AAP + NSAIDs, 0.76% for SD + T, 0.36% for S + M, 0.24% for AOC + NSAIDs, and 0.02% for C + M. In 26% to 58% of episodes of exposure, the two interacting drugs were prescribed by the same physician and dispensed by the same pharmacy the same day. Between 2006 and 2016, the yearly prevalence was increasing for SD + T and for DDIs involving NSAIDs, and it was decreasing for those involving macrolides. CONCLUSION: Exposures to potential DDIs in France are not uncommon with a high proportion resulting from a co-prescription by the same physician. Monitoring the prevalence of exposure to DDIs is needed to implement prevention measures. Administrative data enable this surveillance in large and representative cohorts.

Testicular toxicity following separate and combined administration of PDE5 inhibitors and opioid: assessment of recovery following their withdrawal.

We previously observed that PDE5 inhibitors and opioids were widely abused in Nigeria. Here, we examined the effect of high doses of sildenafil, tadalafil, tramadol and sildenafil + tramadol on reproductive toxicity in male rats. Rats were either administered normal saline (0.2 ml), sildenafil (10 mg/kg), tadalafil (10 mg/kg), tramadol (20 mg/kg) or sildenafil + tramadol (10 and 20 mg/kg respectively) p. o. for 8 weeks. The recovery groups were allowed 8-week recovery period before sacrifice. Results showed that body weight change, testicular and epididymal weights, epididymal sperm count and sperm viability were significantly reduced in all treated groups compared with the control. Spermatozoa with abnormal morphology were significantly increased in all treated groups compared with the control. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) were significantly reduced, while malondialdehyde (MDA) was significantly increased in all treated groups compared with the control. The severity of toxicity was highest in sildenafil + tramadol group. There was no complete recovery from reproductive toxicity following withdrawal of the various treatments. High doses of sildenafil, tadalafil, tramadol or sildenafil + tramadol result in testicular oxidative stress-induced reproductive toxicity with poor reversal following withdrawal.

In vitro and preclinical assessment of factorial design based nanoethosomes transgel formulation of an opioid analgesic.

CONTEXT: Tramadol is a centrally acting analgesic and requires frequent dosing. Hence, judicious selection of retarding formulations is necessary. Transdermal ethosomal gel delivery has been recognized as an alternative route to oral delivery. OBJECTIVE: The objective was to develop statistically optimized ethosomal systems for enhanced transdermal activity of tramadol vis-à-vis traditional liposomes. MATERIALS AND METHODS: Box-Behnken design was employed for optimization of nanoethosomes using phospholipon 90G (A), ethanol (B), and sonication time (C) as independent variables while dependent variables were the vesicle size (Y1), entrapment efficiency (Y2), and flux (Y3). It was prepared by rotary evaporation method and characterized for various parameters including entrapment efficiency, size and transflux. Preclinical assessments were conducted on Wistar rats to measure the performance of developed formulations. RESULTS: The optimized formulation provided mean vesicles size, reasonable entrapment efficiency and enhanced flux when compared with liposome (control). In-vivo absorption study showed a significant increase in bioavailability (7.51 times) compared with oral tramadol. The average primary irritancy index was found to be 1.4, indicating it to be non-irritant and safe for use. DISCUSSION AND CONCLUSION: The results also demonstrated that encapsulated tramadol increases its biological activity due to the superior skin penetration potential. The preclinical study indicates a significant (P < 0.05) extended analgesic effect compared to oral solution using the hot plate test method. The overall results suggest that developed formulation is an efficient carrier for transdermal delivery of tramadol.

Assessment of a carbon dioxide laser for the measurement of thermal nociceptive thresholds following intramuscular administration of analgesic drugs in pain-free female cats.

OBJECTIVE: To assess the potential of a thermal carbon dioxide (CO2) laser to explore antinociception in pain-free cats. STUDY DESIGN: Experimental, prospective, blinded, randomized study. ANIMALS: Sixty healthy adult female cats with a (mean±standard deviation) weight of 3.3±0.6 kg. METHODS: Cats were systematically allocated to one of six treatments: saline 0.2 mL per cat; morphine 0.5 mg kg(-1); buprenorphine 20 µg kg(-1); medetomidine 2 µg kg(-1); tramadol 2 mg kg(-1), and ketoprofen 2 mg kg(-1). Latency to respond to thermal stimulation was assessed at baseline and at intervals of 15-30, 30-45, 45-60, 60-75, 90-105 and 120-135 minutes. Thermal thresholds were assessed using time to respond behaviourally to stimulation with a 500 mW CO2 laser. Within-treatment differences in response latency were assessed using Friedman's test. Differences amongst treatments were assessed using independent Kruskal-Wallis tests. Where significant effects were identified, pairwise comparisons were conducted to elucidate the direction of the effect. RESULTS: Cats treated with morphine (χ2=12.90, df=6, p=0.045) and tramadol (χ2=20.28, df=6, p=0.002) showed significant increases in latency to respond. However, subsequent pairwise comparisons indicated that differences in latencies at specific time-points were significant (p<0.05) only for tramadol at 60-75 and 90-105 minutes after administration (21.9 and 43.6 seconds, respectively) in comparison with baseline (11.0 seconds). No significant pairwise comparisons were found within the morphine treatment. Injections of saline, ketoprofen, medetomidine or buprenorphine showed no significant effect on latency to respond. CONCLUSIONS AND CLINICAL RELEVANCE: The CO2 laser technique may have utility in the assessment of thermal nociceptive thresholds in pain-free cats after analgesic administration and may provide a simpler alternative to existing systems. Further exploration is required to examine its sensitivity and comparative utility.

Brain delivery of intranasal in situ gel of nanoparticulated polymeric carriers containing antidepressant drug: behavioral and biochemical assessment.

This study was aimed for brain delivery of Tramadol HCl (centrally acting synthetic opioid) following intranasal administration for treatment of depression. Chitosan nanoparticles (NPs) were prepared by ionic gelation method followed by the addition of developed NPs with in the Pluronic and HPMC-based mucoadhesive thermo-reversible gel. Developed formulation optimized based on the various parameters such as particle size, entrapment efficiency, in vitro release study. Depression induction was done by forced swim test and evaluated by various behavioral and biochemical parameters. Furthermore, results showed significantly increased in locomotors activity, body weight as compared to control group. It also showed alteration in biochemical parameters such glutathione level and catalase levels significantly increased other than lipid peroxidation and nitrite level was found to be decreased after intranasal administration of formulation. Thus, intranasal TRM HCl NP-loaded in situ gel was found to be a promising formulation for the treatment of depression.

Pharmacoepidemiological assessment of drug interactions with vitamin K antagonists.

PURPOSE: We present a database of prescription drugs and international normalized ratio (INR) data and the applied methodology for its use to assess drug-drug interactions with vitamin K antagonists (VKAs). We use the putative interaction between VKAs and tramadol as a case study. METHODS: We used a self-controlled case series to estimate the incidence rate ratio (IRR) comparing the rate of INR measurements of ≥4.0 in concomitant tramadol and VKA-exposed periods to VKA-only-exposed periods. Secondary analyses considered specific subgroups, alternative exposure criteria, alternative outcome definitions, and other drugs. RESULTS: We identified 513 VKA users with at least 1 INR measurement ≥4.0 and concomitant tramadol and VKA exposure during the observation period. The overall IRR was 1.80 (95% confidence interval [CI], 1.53-2.10), with a stronger association among users of phenprocoumon compared to warfarin (IRR, 3.37; 95%CI, 2.50-4.53 and IRR, 1.46; 95%CI, 1.20-1.76, respectively). We observed larger IRRs with stricter outcome definitions. Concomitant tramadol and VKA exposure was also associated with an increased rate of low INR measurements (i.e., <1.5; IRR, 1.70; 95%CI, 1.37-2.13). Morphine and, to some extent, oxycodone, penicillin, beta-blockers, and inhaled beta-agonists were associated with high INR. CONCLUSIONS: The approach successfully identified an interaction between tramadol and VKA. However, associations observed for other drugs with no known VKA interaction suggest that the current approach may have too low specificity to be useful as a screening tool, at least for drugs for which time-varying confounding may be present.

Basic pharmacology relevant to drug abuse assessment: tramadol as example.

Tramadol is a centrally acting analgesic in widespread use throughout the world. Although there is extensive preclinical, clinical, post-marketing and epidemiological data indicating relatively low--but not zero--abuse/dependence, questions continue to arise about its abuse potential and appropriate regulatory classification. This article considers these questions from the point of view of the basic pharmacology of tramadol. There is nothing unique about tramadol in this regard, but its multimodal mechanism of action, pharmacologically active enantiomers, and active metabolite make it a particularly instructive and relevant example.

Assessment of agonist and antagonist effects of tramadol in opioid-dependent humans.

The subjective, behavioral, and physiologic effects of racemic tramadol, an analgesic with low abuse liability and dual mu-opioid agonist and monoamine reuptake actions, were evaluated in 2 clinical pharmacology studies in dependent opioid abusers. In the withdrawal precipitation study, participants (N = 8) were maintained on methadone 60 mg/day orally and challenged with intramuscular tramadol, hydromorphone, naloxone, and placebo 20 hr after methadone administration. In the withdrawal suppression study, participants (N = 6) were maintained on hydromorphone given orally 10 mg 4 times daily, and spontaneous opioid withdrawal was produced by withholding doses for 23 hr. During the experimentally induced withdrawal, oral tramadol, hydromorphone, naltrexone, and placebo were given. In both studies a comprehensive panel of participant-rated, observer-rated, and physiologic measures were collected. In both studies, naloxone and naltrexone significantly increased measures of opioid withdrawal, whereas tramadol showed no discernible antagonist effects. In contrast, tramadol's pattern of effects was more similar to that of hydromorphone and suggestive of mild opioid-agonist effects (withdrawal suppression), though not to a statistically significant degree.

Perception, assessment, treatment, and management of pain in the elderly.

Twenty to 50% of community elderly suffer from pain. Up to 80% of the institutionalized elderly report at least one pain problem. Multiple pain etiologies that occur in elderly patients may be the occurrence of multiple chronic diseases: osteoarthritis, RA, cancer, DJD, bone/joint disorders, osteoporosis, surgical pain, trauma, neuropathic pain, and nociceptive pain. The incidence of unrelieved pain inhibits respiration, decreases mobility, and decreases their functional status, which may lead to iatrogenic events, which include pneumonia, constipation and deep vein thrombosis. Prolonged inpatient stays and extended care facilities or nursing homes may decrease the elderly patient's expectations of quality of life and initiate social isolation. There exists some roadblocks or barriers to the detection of pain in the elderly client. These include social, emotional, cognitive, and subjective issues with the patient.

Tramadol: does it have a role in emergency medicine?

Tramadol is a synthetic analgesic new to the Australasian market where its use is rapidly increasing. It is used extensively overseas, particularly in Europe where it has been popular since its introduction in Germany in the late 1970s. Tramadol has a dual mechanism of action: weak mu opioid receptor agonist and a reuptake inhibitor of serotonin and noradrenaline. Thus, it has distinct advantages and disadvantages compared to other available analgesics. Its use is advocated in a variety of acute and chronic pain states as well as some non-analgesic applications. The use of tramadol in an emergency setting is not well studied, with most published trials assessing its efficacy and tolerability in postoperative or dental models. This literature review concludes that tramadol does not offer any particular benefits over existing analgesics for the majority of emergency pain relief situations.

Drug interactions with the potential to prevent prodrug activation as a common source of irrational prescribing in hospital inpatients.

OBJECTIVE: Our objective was to investigate the frequency of potential drug-drug interactions between the prodrugs losartan, codeine, and tramadol and drugs known to inhibit their activation in hospitalized patients. METHODS: The frequency of coadministration between losartan and well-established cytochrome P450 (CYP) 2C9 inhibitors, as well as codeine and tramadol and CYP2D6 inhibitors, was studied by use of data from a university hospital medication database. The study population comprised all patients treated in internal medicine, pulmonary medicine, oncology, and neurology wards (105,533 treatment periods and 65,526 patients) between July 1, 1996, and June 30, 2002 (6 years). RESULTS: Every fifth patient receiving losartan, codeine, or tramadol was concomitantly taking another drug that has the potential to inhibit the activation of these drugs. During the 6-year time period, 1999 patients were exposed to a potential interaction. Interactions occurred more commonly in internal medicine wards (odds ratio, 2.3; 95% confidence interval, 2.1-2.5) and in women (odds ratio, 1.5; 95% confidence interval, 1.4-1.7). CONCLUSIONS: Coadministration of drugs that potentially result in inhibition of prodrug activation present a common and unrecognized source of irrational prescribing.

[Comparative study of two Tramadol prescription protocols for postoperative analgesia in children]. / Etude comparative de deux protocoles de prescription du Tramadol pour l'analgésie post opératoire de l'enfant.

We reported the result of a prospective study concerning the use of Tramadol for postoperative analgesia in children. Seventy-two children 1 to 6 year's old were enrolled. Tramadol was given at a dose of 1 mg/kg for 30 minutes and Oral regimen started 4 hours after at a dose of 0.5 mg/kg/6 hours for 24 hours in 40 child. Only one dose of Tramadôl, 2 Mg/kg, was used in other 32 children. We assessed every 3 hours: pain scale (CHEOPS), respiratory rate, and cardiac rate, blood pressure and sedation scale. We obtained satisfactory analgesia in 70% of children since the first hour postoperatively with 2 mg/kg Tramadol and in 60% of them who received 1 mg/kg. In the first group, analgesia had lasted for 24 hours in 62.5% of children and in 80% of children with oral Tramadol. The main side effect was vomiting as reported in 25% of children especially after intravenous Tramadol and mild sedation in 34% of them. Tramadol is a safe and efficient analgesic molecule in children.

Assessment of analgesia in man: tramadol controlled release formula vs. tramadol standard formulation.

OBJECTIVE: The present study tested analgesia produced by a new controlled release formulation of tramadol. The investigation employed an experimental pain model based on chemo-somatosensory event-related potentials (CSSERP) in response to painful chemical stimuli applied to the nasal mucosa. STUDY: Twenty healthy volunteers participated in the experiments, which followed a controlled, randomised, double-blind, 3-way cross-over design. Each of the three medications (tramadol 100 mg [T100], tramadol controlled release 100 mg [TCR100] and tramadol controlled release 150 mg [TCR150]) was administered orally to fasting subjects. There was at least a 6 day washout period between tests. Each experiment was divided into five sessions, which took place before and 2, 4, 6, and 12 h after drug administration. In addition to the assessment of CSSERP, subjects rated the intensity of both the tonic and phasic painful stimuli. Nonspecific drug effects were also monitored by means of frequency analysis of the spontaneous EEG, ratings of adverse effects, and the subjects' performance in a tracking task. RESULTS: The significant reduction of amplitude N1 at central recording positions indicated that TCR 150 was the most effective analgesic 12 h after administration. Both 6 and 12 h after administration TCR 100 was more effective in terms of analgesia compared to T100. In addition, TCR100 appeared to produce fewer adverse effects than the standard formulation of tramadol. CONCLUSIONS: The controlled release formulation can be expected to become a valuable tool in peroral therapeutic regimens for chronic pain.