Double-blind randomized trial of tramadol for the treatment of the pain of diabetic neuropathy. Tramadol in the treatment of neuropathic cancer pain: a double-blind, placebo-controlled study. Maintenance of the long-term effectiveness of tramadol in treatment of the pain of diabetic neuropathy. Efficient assessment of neuropathic pain drugs in patients with small fiber sensory neuropathies. [Treatment of post-herpes zoster pain with tramadol. Results of an open pilot study versus clomipramine with or without levomepromazine]. The effect of tramadol in painful polyneuropathy in relation to serum drug and metabolite levels. Tramadol in post-herpetic neuralgia: a randomized, double-blind, placebo-controlled trial. Open-label study of the safety and effectiveness of long-term therapy with extended-release tramadol in the management of chronic nonmalignant pain. Tramadol/acetaminophen combination tablets for the treatment of chronic lower back pain: a multicenter, randomized, double-blind, placebo-controlled outpatient study.
The objective of this study was to evaluate the efficacy and safety of tramadol in treating the pain of diabetic neuropathy.
                The pain of diabetic neuropathy is a major cause of morbidity among these patients and treatment, as with other small-fiber neuropathies, is often unsatisfactory. Tramadol is a centrally acting analgesic for use in treating moderate to moderately severe pain.
                This multicenter, outpatient, randomized, double-blind, placebo-controlled, parallel-group study consisted of a washout/screening phase, during which all analgesics were discontinued, and a 42-day double-blind treatment phase. A total of 131 patients with painful diabetic neuropathy were treated with tramadol (n=65) or placebo (n=66) tramadol, which were administered as identical capsules in divided doses four times daily. The primary efficacy analysis compared the mean pain intensity scores in the tramadol and placebo groups obtained at day 42 of the study or at the time of discontinuation. Secondary efficacy assessments were the pain relief rating scores and a quality of life evaluation based on daily activities and sleep characteristics.
                Tramadol, at an average dosage of 210 mg/day, was significantly (p < 0.001) more effective than placebo for treating the pain of diabetic neuropathy. Patients in the tramadol group scored significantly better in physical (p=0.02) and social functioning (p=0.04) ratings than patients in the placebo group. No statistically significant treatment effects on sleep were identified. The most frequently occurring adverse events with tramadol were nausea, constipation, headache, and somnolence.
                The results of this placebo-controlled trial showed that tramadol was effective and safe in treating the pain of diabetic neuropathy. To assess the efficacy, safety and impact on quality of life of tramadol in the treatment of neuropathic pain in patients with cancer.
                Patients with similar characteristics were grouped in pairs and randomised to receive either tramadol or placebo. The initial tramadol dosage was 1 mg/kg every 6 hours, increasing to 1.5 mg/kg every 6 hours if necessary to control pain.
                The study enrolled 36 patients (22 women, 14 men), with a mean age of 50 years. In the group receiving tramadol (n = 18), major improvements in pain intensity and Karnofsky scores occurred (p < 0.001), sleep quality improved by day 45 (p < 0.05) activities of daily living improved (p < 0.05), and use of analgesics that had been taken before the study was reduced (p < 0.05) compared with the placebo group. There was no difference between the groups with regard to changes in the Zung Depression Scale, Beck Anxiety Inventory scores and neurophysiological assessments. More patients in the tramadol group experienced adverse events (p < 0.05). The most common adverse events were nausea, vomiting and constipation.
                Tramadol is a therapeutic option for the control of neuropathic pain in patients with cancer, and appears to improve quality of life in these patients. The analgesic effect of tramadol is independent of changes in anxiety, depression and nervous system function. The objective of this study was to evaluate the efficacy and safety of tramadol in a 6-month open extension following a 6-week double-blind randomized trial.
                Patients with painful diabetic neuropathy who completed the double-blind study were eligible for enrollment in an open extension of up to 6 months. All patients received tramadol 50-400 mg/day. Self-administered pain intensity scores (scale 0-4; none to extreme pain) and pain relief scores (scale -1-4; worse to complete relief) were recorded the first day of the open extension (last day of the double-blind phase) and at 30, 90, and 180 days.
                A total of 117 patients (56 former tramadol and 61 former placebo) entered the study. On the first day of the study, patients formerly treated with placebo had a significantly higher mean pain intensity score (2. 2+/-1.02 vs. 1.4+/-0.93, P<0.001) and a lower pain relief score (0. 9+/-1.43 vs. 2.2+/-1.27, P<0.001) than former tramadol patients. By Day 90, both groups had mean pain intensity scores of 1.4, which were maintained throughout the study. Mean pain relief scores (2. 4+/-1.09 vs. 2.2+/-1.14) were similar after 30 days in the former placebo and former tramadol groups, respectively and were maintained for the duration of the study. Four patients discontinued therapy due to ineffective pain relief; 13 patients discontinued due to adverse events. The most common adverse events were constipation, nausea, and headache.
                Tramadol provides long-term relief of the pain of diabetic neuropathy. We sought to develop an enrichment crossover study design that would allow us to efficiently evaluate and compare promising candidate neuropathic pain drugs. We evaluated the efficacy of gabapentin or tramadol vs. active placebo (diphenhydramine) in subjects with biopsy-proven painful idiopathic small fiber neuropathy (SFN) who were self-reported gabapentin responders. Eligible subjects entered two single blind run-in phases. In the first phase (Period A), subjects were treated with single blinded gabapentin at their prestudy dose followed by a second run-in phase (Period B) in which they were treated with diphenhydramine active placebo. Subjects with >or=3 pain and a >or=30% increase in pain intensity in Period B compared to Period A were then randomized to a double-blind three period cross over trial of gabapentin at pre study dosage, tramadol 50mg QID and diphenhydramine 50mgqhs. Of the 59 subjects enrolled, 41 subjects were excluded: Twenty-three had an insufficient rise in pain intensity in Period B; eight had skin biopsies that did not confirm SFN. Eighteen subjects were randomized into the double-blind, crossover phase. There was a significant treatment effect of gabapentin vs. diphenhydramine (p=0.001) and tramadol vs. diphenhydramine (p=0.018) by the before-bed daily pain score averaged over the final 7 days of each treatment period. We conclude that gabapentin and tramadol were effective in the treatment of painful SFN and that this experimental enrichment paradigm is attractive to screen potential neuropathic pain compounds for efficacy in proof-of-concept studies. To date, no universally applicable recommendations are available for the treatment of patients with postherpetic neuralgia. A mixture of clinical anecdotes, experimental findings and observations from clinical trials form the basis of the medical arsenal for this condition. Tricyclic antidepressants are commonly used, and clinical experience and several investigations have documented their effectiveness. Today, single entity antidepressants, which can be combined with neuroleptics to increase analgesia, are generally recommended for the treatment of postherpetic neuralgia. Some authors also recommend the additional administration of an opioid if analgesia is inadequate. Just over a decade ago, opioids were considered ineffective for the treatment of neuropathic pain; however, more recent investigations relating to the use of opioids, primarily in the treatment of nontumour-related chronic pain, have led to a revision of their use in neuropathic pain. Nevertheless, the use of opioid therapy for neurogenic pain remains controversial. Tramadol is a synthetic, centrally acting analgesic with both opioid and nonopioid analgesic activity. The nonopioid component is related to the inhibition of noradrenaline (norepinephrine) reuptake and stimulation of serotonin (5-hydroxytryptamine; 5-HT) release at the spinal level. In this regard, there are parallels with antidepressants, which are believed to potentiate the effect of biogenic amines in endogenous pain-relieving systems. There is evidence that, in tramadol, both mechanisms act synergistically with respect to analgesia. The aim of this pilot study was to investigate, for the first time, the analgesic efficacy and tolerability of tramadol, compared with the antidepressant clomipramine, in the treatment of postherpetic neuralgia. If necessary, clomipramine was used in combination with the neuroleptic levomepromazine. The study allowed individualised dosages at predetermined intervals up to a maximum daily dose of tramadol 600mg and clomipramine 100mg, or clomipramine 100mg with or without levomepromazine 100mg. 21 (60%) of 35 randomised patients (> or = 65 years) received the study medication over the 6-week period [tramadol n = 10; clomipramine with or without levomepromazine) n = 11]. After 3 weeks' treatment the dosage in both groups remained almost constant for the rest of the 6-week treatment phase (mean daily dose: tramadol 250 to 290mg; clomipramine 59.1 to 63.6mg). Only 3 patients required the combination of clomipramine and levomepromazine. At the outset, both groups recorded an average pain level of 'moderate' to 'very severe'. In correlation with increasing the study medication, this had decreased to 'slight' by the end of the treatment, when 9 of 10 patients in the tramadol group and of 6 of 11 patients in the clomipramine group retrospectively rated their analgesia as excellent, good or satisfactory. The psychological/physical condition of the patients did not change significantly during tramadol treatment. Sensitivity and depression parameters decreased in the clomipramine group. The incidence of adverse events for all patients was similar in both groups (tramadol 76.5%; clomipramine with or without levomepromazine 83.3%). In conclusion, tramadol would appear to be an interesting therapeutic alternative for pain relief in postherpetic neuralgia, particularly in patients who are not depressed. In clinical practice, tramadol and clomipramine can best be used differentially. For example, tramadol could be the drug of first choice in patients with obvious cardiovascular disease (not an uncommon problem in the > or = 65 year age group) in whom antidepressants are contraindicated, and similarly in patients in whom an antidepressant effect is not required. (ABSTRACT TRUNCATED) Tramadol is a racemic drug that may act through a monoaminergic effect of (+)- and (-)-tramadol and through an opioid effect of its metabolite (+)-Ml. The objective of this study was to investigate the relationship between relief of pain and serum concentrations of tramadol and Ml in tramadol treatment of painful polyneuropathy.
                In a randomized, double-blind, placebo-controlled trial of 200 to 400 mg/day tramadol, serum concentrations of (+)- and (-)-tramadol and (+)- and (-)-Ml were determined in 28 of 34 patients. Ongoing and touch-evoked pain was rated daily by the patients by use of 0- to 10-point numeric rating scales during two 4-week treatment periods.
                Tramadol significantly reduced both on-going (P = .002) and touch-evoked pain (P < .001). There was no relation between relief of on-going and touch-evoked pain and serum concentrations of (+)-tramadol, (-)-tramadol, (+)-M1, or (-)-M1 (P = .11 to P = .89). Seventeen of the patients were categorized as responders for on-going pain and 16 for touch-evoked pain. Responders for on-going pain tended to have higher serum concentrations of (+)-Ml than nonresponders (median, 27 nmol/L versus 16 nmol/L; P = .08). Isobolograms showed that the fraction of nonresponders was higher among patients with low concentrations of both tramadol and (+)-Ml both for on-going (P = .009) and touch-evoked (P = .02) pain.
                The opioid effect of (+)-Ml may be of importance for tramadol relief of on-going neuropathic pain but, in general, relief of neuropathic pain seems to depend on both the monoaminergic effect of (+)- and (-)-tramadol and the opioid effect of (+)-Ml. The efficacy and safety of sustained-release tramadol compared to placebo in the treatment of post-herpetic neuralgia were evaluated in a multicenter, randomized, double-blind, parallel-group study in 127 outpatients. Treatment was administrated for 6 weeks. The dose of tramadol could be increased from 100 mg/day to 400 mg/day (300 mg/day in patients more than 75 years old). Groups were compared on changes in pain intensity on a Visual Analogue Scale (VAS) between inclusion and the 6th week of treatment (covariance analysis as main analysis and repeated measures analysis as complementary analysis) in the per protocol (PP) population. The randomized population comprised 127 patients aged 35-85 years, mostly females (72.4%). Groups were comparable at inclusion both in the intent to treat (ITT) population (63 patients in the tramadol group and 62 patients in the placebo group) and in the PP population (53 patients in the tramadol group and 55 patients in the placebo group). Mean pain intensity on day 43 adjusted on day 1 (covariance analysis) was significantly lower in the tramadol group than in the placebo group in both the PP (P=0.0499), and the ITT (P=0.031) populations. The two groups significantly differed on change in pain intensity over time (repeated measures analysis) in the ITT population (P=0.012). The percentage of pain relief over the 6th week was significantly higher in the tramadol group than in the placebo group (P=0.017). During the 6th week, patients in the tramadol group required less rescue medication than patients in the placebo group (P=0.022). No significant difference was found between groups either in pain intensity on a 5-point Verbal Scale (VRS) or in quality of life measurements. Tramadol was administered at an average dosage of 275.5 (89.7) mg/day after a 1-week dose-adaptation period. Tramadol was well tolerated. No notable difference appeared between groups either in the percentage of patients with treatment-associated adverse events (TAAE) (29.7% in the tramadol group and 31.8% in the placebo group) or in the total number of TAAE (31 in the tramadol group and 28 in the placebo group). Tramadol ER* is a once-daily oral analgesic for management of moderate-to-moderately severe chronic pain in adults who require around-the-clock treatment of pain. This study evaluated long-term safety of tramadol ER and effectiveness outcomes in the management of chronic, nonmalignant pain.
                Patients enrolled directly for approximately 1 year of open-label tramadol ER treatment if they had chronic, nonmalignant pain (n = 919), or 'rolled over' for 38 weeks of open-label tramadol ER treatment if they completed either of two 12-week, placebo-controlled studies of tramadol ER for low back pain (n = 72) or osteoarthritis (n = 61). Tramadol ER was titrated to a dose of 300 mg once daily (patients >or= 75 years) or 300-400 mg once daily (patients < 75 years).
                A total of 257 (24%) patients completed the study. Common adverse events, regardless of treatment relationship, were nausea, dizziness (excluding vertigo), and constipation. Mean scores for current pain intensity (from 0 = no pain to 100 = extreme pain) and least, worst, and average pain intensity over the past week improved at every post-baseline visit. At each post-baseline visit, > 50% of patients provided a global assessment rating of good, very good, or excellent. Study limitations were mandatory titration to 400 mg in some patients, concomitant analgesic therapy as a confounding variable, and lack of a placebo comparator.
                Individualized dose titration and limiting once-daily therapy with tramadol ER to the maximum recommended daily dose of 300 mg may balance tolerability and analgesic effects of tramadol ER in patients with chronic, nonmalignant pain. Tramadol and acetaminophen (APAP) have both shown efficacy in the treatment of lower back pain. The combination of these 2 agents has demonstrated synergistic analgesic action in animal models at specific ratios.
                This study assessed the long-term (3-month) efficacy and safety of tramadol 37.5 mg/APAP 325 mg combination tablets in the treatment of chronic lower back pain.
                Patients with at least moderate lower back pain (pain visual analog [PVA] score >/=40 mm on a 100-mm scale) were randomized to receive up to 8 tablets of tramadol/APAP per day or placebo for 91 days. Medication was titrated from 1 to 4 tablets/d by day 10. The primary efficacy measure was PVA score at the final visit. Secondary measures included scores on the Pain Relief Rating Scale (PRRS), Short-Form McGill Pain Questionnaire (SF-MPQ), Roland Disability Questionnaire (RDQ), and 36-Item Short-Form Health Survey (SF-36); the incidence of discontinuation due to insufficient pain relief (Kaplan-Meier analysis); and overall assessments of medication by the patients and investigators.
                Three hundred eighteen patients (161 tramadol/APAP, 157 placebo) were included in the intent-to-treat population, defined as all patients who took >/=1 dose of study medication and had >/=1 postrandomization efficacy measurement. The mean age of the study population was 53.9 years, 63.2% were female, 90.3% were white, and the mean baseline PVA score was 70.0 mm. There were no significant differences between groups at baseline. Tramadol/APAP significantly improved final PVA scores (P = 0.015) and final PRRS scores (P < 0.001) compared with placebo. Tramadol/APAP also significantly improved RDQ scores (P </= 0.027) and scores on many subcategories of the SF-MPQ, including total score (P = 0.021). The tramadol/APAP group had significant improvements on the role-physical (P = 0.005), bodily pain (P = 0.046), role-emotional (P = 0.001), mental health (P = 0.026), reported health transition (P = 0.038), and mental component summary (P = 0.008) subscales of the SF-36. The cumulative incidence of discontinuation due to insufficient pain relief was 22.1% for tramadol/APAP and 41.0% for placebo (P < 0.001). Treatment-emergent adverse events in the tramadol/APAP group included nausea (13.0%), somnolence (12.4%), and constipation (11.2%).
                In this study, tramadol 37.5 mg/APAP 325 mg combination tablets were effective and had a favorable safety profile in the treatment of chronic lower back pain.
Tramadol is an effective treatment for neuropathic pain.