Showing papers on "Buprenorphine published in 1985"

Clinical actions of fentanyl and buprenorphine. The significance of receptor binding.

Abstract: Receptor binding assays were undertaken in an attempt to elucidate the opioid binding characteristics of fentanyl and buprenorphine, and to investigate some of the differences between them. Buprenorphine showed slow receptor association (30 min), but with high affinity to multiple sites from which dissociation was very slow (T½ = 166 min) and incomplete (50% binding after 1 h). This contrasted with the receptor binding of fentanyl, which achieved rapid equilibrium (within 10 min) and dissociated equally rapidly (T½ = 6.8 min) and completely (100% by 1 h). Competitive displacement showed buprenorphine displacement of fentanyl binding was concentration-and time-dependent over ranges encountered in clinical use, but buprenorphine binding was displaced with only very high concentrations of other opioids. These findings offer pharmacodynamic explanations for the differences in fentanyl and buprenorphine analgesic response profiles and suggest how binding interactions might be applied to therapeutic use.

Epidural opiates: Long-term experiences in cancer pain

Abstract: Epidural opiates were administered to 139 patients with pain due to malignant diseases via a chronic indwelling catheter inserted percutaneously. So far, 9,716 days of treatment can be evaluated. In 87% of the patients whose pain previously could not be controlled with conventional analgesic approaches, epidural opiates resulted in remarkable pain relief. With a mean daily dose of 15.6 mg morphine (range 2–290 mg) or 0.86 mg buprenorphine (range 0.15–7.2 mg) half of the patients could be treated as outpatients. The mean duration of therapy was 72 days (range 1–700 days), 26 catheters being in place for more than 100 days and one catheter being in place for 501 days. Two severe side-effects (meningitis) were observed, both patients being free of symptoms after catheter removal and antibiotic therapy. Epidural opiates proved to be a valuable method of pain control in terminal illness. The method should be reserved for those patients, for whom oral opiates fail to produce effective pain relief.

Buprenorphine effects on cigarette smoking.

Abstract: Cigarette smoking increased during administration of buprenorphine, an opioid mixed agonist-antagonist, in comparison to drug-free baseline in seven heroin addicts maintained on buprenorphine for 24 days (P<0.01–0.001). Ascending buprenorphine doses (0.5–8.0 mg/day) were associated with significant increases in cigarette smoking at doses of 2.0 mg/day sc and above. Cigarette smoking during 10 days of buprenorphine maintenance at 8 mg/day was significantly higher than during the buprenorphine induction phase (P<0.01). Six subjects given placebo buprenorphine over 14 days showed no change in cigarette smoking. The placebo group self-administered heroin for 10 days, and cigarette smoking increased significantly during heroin use (P<0.001). The rate of cigarette smoking defined by intercigarette intervals was highest during the 10 days of high-dose buprenorphine maintenance or placebo plus heroin self-administration. Both groups requested significantly more cigarettes at intervals of 0–10, 11–20, and 21–30 min than during the drug-free baseline. These data confirmed previous findings that opioid agonist administration is associated with increased cigarette smoking and suggest that buprenorphine has primarily agonist effects on cigarette smoking.

Meptazinol. A review of its pharmacodynamic and pharmacokinetic properties and therapeutic efficacy.

Abstract: Meptazinol is a new opioid-type analgesic with mixed agonist/antagonist properties. It may be given orally, intravenously or intramuscularly. In studies in patients with moderate to severe pain of various aetiologies, usually following surgery or in obstetrics, the characteristics of analgesia with meptazinol were comparable to those seen with equianalgesic doses of pentazocine, pethidine or a combination of dextropropoxyphene and paracetamol. Preoperative use and use as a component of anaesthesia require further investigation before conclusions may be drawn on its effectiveness in these areas. Onset of action, recorded in a few studies, was faster than that with the other analgesics but duration was shorter than that of morphine, buprenorphine and pentazocine. Only a small number of patients with chronic pain have received long term therapy with meptazinol; in such patients there was no need for increased doses as treatment progressed. Respiratory depression has only been observed in patients receiving meptazinol as a premedication or while undergoing anaesthesia. Similarly any haemodynamic changes have been limited to preoperative patients or patients undergoing anaesthesia. Like other agonist/antagonist analgesic drugs, the abuse potential of meptazinol seems relatively low, but only wider clinical use for longer periods can establish this with certainty. The most commonly reported side effects have been gastrointestinal in nature, and although the incidence of central nervous system side effects has been relatively low, drowsiness and dizziness have caused occasional problems. Thus, meptazinol is a relatively potent but safe addition to the analgesics available for treatment of the patient with moderate to severe pain.

Buprenorphine is an Antagonist at the ϰ Opioid Receptor.

Abstract: The effect of buprenorphine on bremazocine-induced diuresis was tested in the rat to determine the nature of buprenorphine's action at the ϰ opioid receptor. Both morphine-tolerant and naive rats were used to account for possible antidiuretic effects of buprenorphine at the µ site. Separate experiments established that the morphine pretreatment caused profound tolerance with respect to the antidiuretic action of µ agonists. Buprenorphine acted as a potent antagonist (ID50 = 11µg/kg) of the diuretic action of the ϰ agonist bremazocine (ED50 = l0 µg/kg). The similar potency of buprenorphine as an antagonist of bremazocine in naive and morphine-tolerant rats further supports the hypothesis that buprenorphine exerts it's antidiuresis via an antagonistic effect at ϰ sites, rather than as an agonist at the µ sites. The high affinity displayed by buprenorphine at the ϰ opioid receptor in vivo is consistent with this conclusion. Hence, buprenorphine can now be classified as a partial agonist at the µ site and as an antagonist at the ϰ site against bremazocine induced urine flow, while its action at the δ site to which it has much lower affinity in vivo remains unknown.

Disposition in the rat of buprenorphine administered parenterally and as a subcutaneous implant

Abstract: Disposition of [15, 16(n)-3H]buprenorphine in the rat has been investigated after a single 0.2 mg/kg i.v. bolus dose and continuous administration via a s.c. implantable long-acting delivery system. After the i.v. injection, the tri-exponential decay of drug from brain occurred with t1/2 values of 0.6, 2.3 and 7.2 h, respectively (plasma t1/2 0.5, 1.4 h, third phase not estimated due to sustained concn.) Decay of drug from another high-affinity binding site in brain occurred with t1/2 values of 1.1 and 68.7 h, respectively. Fat and lung had higher concn. than other tissues and plasma. No metabolites of drug were detected in brain. Unmetabolized drug excreted in urine and faeces one week after i.v. injection were 1.9 and 22.4% of dose, respectively, and 92% of the dose was accounted for in one week. Urinary metabolites (%) were: conjugated buprenorphine 0.9; norbuprenorphine (free 9.4, conjugated 5.2); tentative 6-O-desmethylnorbuprenorphine (free 5.4, conjugated 15.9). Peak plasma concn. of buprenorphine occurred four weeks after s.c. implantation of a long-acting 10 mg 3H-buprenorphine pellet, and apparent dissociation half-lives of drug from low- and high-affinity binding sites in brain were 4.6 and 6.8 weeks, respectively. Fat, spleen and skeletal muscle had higher concn. than other tissues and plasma. No significant difference in brain morphine concn. was observed in placebo and nonlabelled buprenorphine-pelleted animals after a 2 mg/kg i.v. challenge dose of 3H-morphine. This study emphasizes the importance of high-affinity binding of buprenorphine in brain and subsequent slow dissociation as a prime factor in its prolonged agonist/antagonist effects and higher potency than other narcotic agonists.

Sublingual buprenorphine for premedication and postoperative pain relief in orthopaedic surgery.

Abstract: The effect of sublingual buprenorphine (Temgesic) as a premedicant and for postoperative pain relief compared with morphine/pethidine was studied in 50 patients scheduled for elective surgery of the knee joint. Twenty-five patients received buprenorphine 0.4 mg sublingually 1 h before surgery and the same dose on demand postoperatively. Twenty-five patients were given morphine intramuscularly (7.5 mg or 10 mg to females and males respectively) 1 h preoperatively. This group received pethidine (75 mg) intramuscularly on demand postoperatively. All the patients were anaesthetized with halothane N2O/O2 after induction with thiopentone. No significant differences were found with regard to sedation, dizziness, nausea and vomiting during the study period. Emergence shivering, confusion and restlessness just after termination of the operation were equal in the two groups. In the recovery room, however, there was a higher frequency of shivering (P less than 0.05) in the morphine group. During the first 24 h postoperatively the buprenorphine group was given an average of 3.8 doses compared with 2.3 in the pethidine group (P greater than 0.05). It is concluded, that buprenorphine sublingually is as good as morphine intramuscularly for premedication and therefore should be recommended to patients who wish to avoid injections. For postoperative pain relief the initial dose of buprenorphine should be given intravenously. Only minor and unimportant side effects were seen.

Buprenorphine in end stage renal failure.

Abstract: A number of studies have now served to emphasise the dangers of prescribing opioid drugs in end stage renal failure patients. Buprenorphine is a strong analgesic which may be given ~ublingually;~ it has high systemic clearances and presumed, largely hepatic metabolism. It should therefore be safe in patients with abnormal renal function. We have studied the kinetics of buprenorphine in five patients with end stage renal failure. Buprenorphine 0.3 mg was injected intravenously into a peripheral vein over one minute. Arterialised blood samples were withdrawn before injection and at time intervals to 180 minutes. Drug concentrations were measured by a specific radioimmunoassay technique and the plasma centrations werecompared to the 95% confidence limits of the healthy group, three of the five patients with end stage renal failure lay outside these limits. The AUCo for the five renal patients was 533 min.ng/ml (SEM 116), and for the 10 healthy patients 246 min.ng/ ml (SEM 18); these were not significantly different. The (p < 0.02) than the postoperative patients and had altered biochemical and haematological tests: mean (SEM) urea 30.7 (3.6) mmol/litres; mean (SEM) creatinine 1109 (160) ymol/litre; mean (SEM) haemoglobin 8.8 (1.2) gm/dl. Figure 1 shows the individual data from the five patients with end stage renal failure, together with the mean (SEM) for the healthy postoperative patients (hatched area). There were no significant differences between the mean concentrations of the two groups, except at 5, 10, 15, 20 and 80 minutes after injection (p < 0.05 to p < 0.001). When the individual patient concentrations were compared to the 95% confidence limits of the healthy group, three of the five patients with end stage renal failure lay outside these limits. The A U C O ~ for the five renal patients was 533 min.ng/ml (SEM 116), and for the 10 healthy patients 246 min.ng/ml (SEM 18); these were not significantly different. The end stage renal failure patients showed no clinical evidence of sedation or respiratory depression throughout the duration of this study. There are a number of caveats: altered haemodynamics, age and altered regional blood flow following surgery, but this study is important for two reasons. Firstly, it demonstrates the lack of any significant difference in the distribution of buprenorphine in our two groups. Secondly, there were no clinical sequelae. This is in contrast to the altered distribution with prolonged sedation and respiratory depression seen when morphine and its cogeners are used in end stage renal failure patients. Buprenorphine in these patients would, therefore, appear worthy of further study with a longer sampling period. 0 60 I20 180 Mi nutrs

Epidural buprenorphine — A double-blind study of postoperative analgesia and side effects : Anesth. Analg., 63 (1984) 593–598

Abstract: Epidural buprenorphine was investigated as a postoperative analgesic in a randomized double-blind study of 158 patients given epidural analgesia with mepivacaine or bupivacaine for orthopedic surgery of the lower extremity. At the end of surgery, patients were given either 0.15 mg of epidural buprenorphine (n = 38), 0.3 mg (n = 37) in 15-ml saline, or no further epidural injections (n = 47, control group) after 2% mepivacaine for intraoperative anesthesia. A fourth group (n = 36) received 0.3 mg of buprenorphine in 15-ml saline, after the intraoperative use of 0.5% bupivacaine. The patients rated postoperative pain. The need for additional analgesics as well as side effects were recorded. Analgesia after 0.15 mg buprenorphine was superior to that after no reinjection for 6 hr after surgery (P less than 0.05). Buprenorphine (0.3 mg) was superior both to no reinjection and to 0.15 mg of buprenorphine until the twelfth hour (P less than 0.05). Analgesia after bupivacaine followed by 0.3 mg of buprenorphine was not significantly different than analgesia seen after mepivacaine followed by 0.3 mg of buprenorphine. There was an increase of PaCO2 of 2-5 mm Hg between 1.5-3.5 hr after 0.3 mg of buprenorphine without any evidence for late respiratory depression. Other side effects, e.g., disturbances of micturition, pruritus, nausea, vomiting, fatigue, and headache, were comparably common in all groups. The epidural administration of 0.3 mg buprenorphine may be recommended for postoperative analgesia following orthopedic surgery of the lower extremity.

EFFICACY OF THE EXTRADURAL ADMINISTRATION OF LOFENTANIL, BUPRENORPHINE OR SALINE IN THE MANAGEMENT OF POSTOPERATIVE PAIN A Double-blind Study

Abstract: Sixty postoperative orthopaedic patients were randomly assigned to three equal groups to study, in a double-blind fashion, the analgesic effects, durations of action and side effects of the extradural administration of lofentanil 5 μg, buprenorphine 0.3 mg or physiological saline. No systemic analgesics were given before, during or after surgery, and all the patients had operations on the lower extremities under extradural analgesia (lignocaine and bupivacaine). Eleven milli-litre of the test drug was injected at T12-L1 as soon as pain occurred in the postoperative period. We observed a long duration of action and a marked analgesic effect with lofentanil, a shorter duration of action and less pain suppression with buprenorphine and a rather marked placebo effect after saline. The only side effect noticed in this study was drowsiness in three patients in the lofentanil group and in two patients in the buprenorphine group.

Pharmacological Advances in Addiction Treatment

Abstract: In the past 20 years significant advances in the pharmacological treatment of opioid dependence have been made, and research in this area is continuing. Therapeutic applications and current research in the use of pharmacological agents in maintenance therapy, treatment with narcotic antagonists, and narcotic detoxification are discussed. In addition, an overview is presented of recent developments in opioid pharmacology and of recently developed novel pharmacological agents which may prove useful in the future treatment and/or prevention of opioid dependence.

Effects of buprenorphine on shock titration in squirrel monkeys.

Abstract: The effects of buprenorphine were examined under a shock titration procedure and compared to the effects of morphine. Under this procedure shock increased every 15 sec from 0 to 2.0 mA in 30 increments. Five responses within a 15-sec shock period decreased shock intensity by one increment. Both buprenorphine and morphine increased the level at which shock was maintained without decreasing rates of responding in the presence of shock. Buprenorphine-induced increases in median shock level occurred over a 10-fold dose range and were apparent for 6 to 12 hr. Dose-effect curves for morphine and buprenorphine were shifted to the right by prior administration of diprenorphine (0.001-1.0 mg/kg), naloxone (0.001-1.0 mg/kg) and beta-funaltrexamine (1.0-16.0 mg/kg), with the dose of antagonist required to restore responding to control levels being 1 to 2 log U larger for buprenorphine than for morphine. Buprenorphine-induced increases in median shock level were also restored to control levels when naloxone (1.0 mg/kg) was administered as much as 110 min after buprenorphine. Buprenorphine was not effective in antagonizing the effects of morphine. When a dose of buprenorphine which increased median shock level was administered once daily, median shock levels returned to control level within 6 to 15 days. When the morphine dose-effect curve was then redetermined in the presence of chronic buprenorphine, it exhibited a 10-fold shift to the right.

A long-term open, clinical and pharmacokinetic assessment of sublingual buprenorphine in patients suffering from chronic pain.

Abstract: Buprenorphine was administered as sublingual tablets to 70 patients suffering from chronic pain of malignant or non-malignant origin. Daily doses ranging from 0.4 mg to 3.2 mg were administered and good analgesia was reported by the majority of patients. The most common unwanted effects were drowsiness/sleepiness, nausea and/or vomiting and sweating which appeared to be dose related but the incidence of dizziness was not related to daily dose. The incidence of all these unwanted effects except drowsiness/sleepiness decreased after the first week's treatment. No buprenorphine related changes in vital signs or laboratory values were observed and no signs of tolerance or physical dependence were seen in the short term period after discontinuation of treatment. A significant positive correlation between buprenorphine plasma concentration and daily dose was observed but there was no correlation between plasma levels and pain relief.

Buprenorphine effects on food-maintained responding in Macaque monkeys

Abstract: The effects of acute and chronic administration of buprenorphine, an opioid mixed agonist-antagonist, on food-maintained responding were compared in Macaque monkeys Low acute doses of buprenorphine (001 and 003 mg/kg) did not change the number of food pellets earned or response rates on an FR 4 (VR 16:S) schedule of reinforcement from saline pre-treatment levels Acute administration of 010 and 030 mg/kg buprenorphine significantly suppressed food-maintained responding (p less than 001) Chronic buprenorphine self-administration (001-010 mg/kg/injection) did not significantly suppress food intake, even at total daily doses that were 3 to 9 times higher than the highest dose (003 mg/kg) studied in the acute pre-treatment paradigm Decreases in daily buprenorphine intake to 30 to 40 percent of control levels were not associated with increased food self-administration Similarly, chronic heroin self-administration (001, 005, and 010 mg/kg/injection) was not associated with significant changes in food self-administration These data suggest that during chronic self-administration of buprenorphine Macaque monkeys developed tolerance to its acute suppressive effects on food-maintained responding

Buprenorphine Delays Drug Absorption and Gastric Emptying in Man

Abstract: The aim of the present study was to investigate the effects of buprenorphine on drug absorption and gastric emptying in man, using paracetamol absorption as an index of gastric emptying rate. Paracetamol was given to eight healthy volunteers p.o. together with or without a single i.v. dose of buprenorphine 4 micrograms kg-1 body weight. Nausea occurred in five of the subjects, four subjects vomited and one was excluded due to vomiting during the study period. The mean peak serum paracetamol concentration (Cmax) was significantly (P less than 0.0002) lowered by a factor 3 by buprenorphine, the mean time from administration of paracetamol to its peak concentration (Tmax) was significantly (P less than 0.03) prolonged by a factor 6, and the area under the plasma concentration-time curve from 0 to 120 min was significantly (P less than 0.00006) reduced by a factor 3. This demonstrates a marked inhibition of the rate of paracetamol absorption, indicating a clinically important reduction of gastric emptying following administration of buprenorphine.

Regular interval preventive pain relief compared with on demand treatment after hysterectomy

Abstract: Eighty otherwise healthy women, aged 22-64 years, admitted for elective hysterectomy were studied in a prospective randomized trial. The aim was to compare two different postoperative pain relief schedules--one with the analgesic given at regular intervals and the other with the analgesic given on demand. All the patients had a neuroleptanaesthesia with fentanyl. Forty patients received an initial dose of buprenorphine 0.3 mg intravenously before termination of anaesthesia and continued with sublingual buprenorphine 0.4 mg 6 hourly postoperatively (regular interval (RI) group). Forty patients received the standard postoperative medication, meperidine 1 mg/kg on demand in the recovery room, followed by ketobemidone 5 mg subcutaneously on demand in the surgical ward (on demand (OD) group). There was no difference between groups concerning pain relief following a single dose of analgesic (P greater than 0.05, type II error 1-5%). In the recovery room 17.5% of the patients in the RI group received an analgesic compared to 87.5% in the OD group (P less than 0.05). Among patients in the RI group who had previously got injections for postoperative pain relief on demand 95% preferred regular interval sublingual buprenorphine for future treatment. The nurses found that 90% of the patients in the RI group were treated adequately compared to 62.5% of the patients in the OD group (P less than 0.05). It is concluded, that regular interval preventive pain relief is superior to conventional on demand analgesic therapy in postoperative pain.

Epidural buprenorphine for postoperative pain relief.

Abstract: We would like to comment on the recent article by Lanz et al. (Anesth Analg 1984;63:.593-8) on the use of epidural buprenorphine for pain relief after major orthopedic surgery. Over the last few years we have gained considerable experience with the use of buprenorphine administered into the epidural space and we have found our results to be somewhat at variance with those of Lanz and his associates. It is our contention that the benefits of epidural and intradural (subarachnoid) opiate administration accrue from the high quality of analgesia provided at very low dosage. It seems, therefore, unnecessary and illogical to use the same dosage of opiate in the epidural space as for intramuscular or intravenous injection. We have used a dosage of 60 pg (0.06 mg) of epidural buprenorphine diluted to 10 ml with physiological saline and compared this with the analgesic efficacy of intramuscular morphine (0.15 mg/kg) and epidural morphine (2 mg diluted to 10 ml) in patients after major hip, major spinal, and major abdominal surgery (1-3). Our results indicate that 60 pg of epidural buprenorphine repeated when necessary (rarely more frequently than every 8 hr) provides consistent and satisfactory analgesia when using this technique as the sole means of postoperative analgesia. Lanz et al. found that patients receiving 0.15 mg of epidural buprenorphine had less pain than their control group, and those given 0.3 mg of buprenorphine fared best of all. Surely it comes as no surprise that those given opiates for postoperative pain suffered less pain than those given nothing. This does not prove that epidural buprenorphine works. To prove that spinal opiates work by a local (spinal) effect it is necessary to show that analgesia thus provided is done so at a dosage that would be insufficient when given by the usual parenteral routes. It is similarly not surprising to learn that a dosage of 0.3 mg has a longer duration of action than half that dosage. Elementary pharmacokinetic principles of drugs following first order kinetics provide the answer to this effect. A rational response to such an effect would be to “top-up” the epidural as necessary. The authors noted that Pacoz values in control patients and in those receiving epidural buprenorphine remained within the normal range. They then noted that ‘Tacoz levels after 0.3 mg buprenorphine epidurally were slightly but significantly greater ( P < 0.0.5).” There follows in the discussion section of their paper a full paragraph on the possible explanation of this statistical fact. If Pacoz values remained within a normal range surely it is sufficient to document this fact. Statistically significant differences within a normal range of results have no meaning in a clinical setting. There have been many studies (4-8) using highly sensitive methods of assessing respiratory effects of epidural opiates (e.g., CO, response curves and measurement of mouth occlusion pressures) and all have shown that some loss of CO, sensitivity occurs. We believe that this merely demonstrates that opiate administration by any route, including epidural and intradural (subarachnoid), will be followed by respiratory depression, if a method of assessment is sufficiently sensitive to detect it. Opiates cause respiratory depression. What is important i s whether or not this is clinically significant. Lanz et al. have shown in their paper that it is not. We have similarly documented this fact (4). Finally, the authors make an unsubstantiated statement that “the effective epidural and intravenous doses of buprenorphine do not differ.” This is not so. There is to date in the literature no scientific comparison of the potencies of epidural and intravenous buprenorphine. In an ongoing study, we are presently comparing the use of epidural buprenorphine with intravenous buprenorphine for pain relief in patients after thoracotomy. Our results to date indicate that significantly more buprenorphine is required by patients receiving the drug intravenously. Furthermore, we are measuring plasma levels of buprenorphine after its administration by either route and we have found significantly smaller plasma levels after epidural administration. These studies are reaching completion and shortly will be ready for publication.

Comparison of hemodynamic effects of morphine, butorphanol, buprenorphine and pentazocine on ICU patients.

Abstract: Morphine and narcotic agonist-antagonists have been used to assist ICU patients in adapting to mechanical ventilation. In this study, 10 mg of morphine and the equipotent doses of synthetic analgesics, 2 mg of butorphanol, 0.6 mg of buprenorphine or 30 mg of pentazocine were administered intravenously to 29 patients requiring a ventilator. Hemodynamic effects on the heart rate, mean arterial pressure (MAP), cardiac index, stroke index, left ventricular stroke work index, mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP) and systemic and pulmonary vascular resistance (PVR) were measured. The hemodynamic effects of the four drugs were mild and not statistically significant except for the reduction in PCWP and the increase in PVR after morphine and the increase in MAP and MPAP after pentazocine administration. These doses of the four drugs could be given safely even in critically ill patients. The hemodynamic effects of these analgesics showed a similarity between the administration of butorphanol and morphine, and between buprenorphine and pentazocine. This study demonstrates that morphine and butorphanol are preferred to the cases with hypertension, increased pulmonary arterial pressure or wedge pressure and that pentazocine and buprenorphine are more suitable for the cases with hypotension or hypovolemia.

BUPRENORPHINE-SUPPLEMENTED ANAESTHESIA Influence of Dose on Duration of Analgesia after Cholecystectom

Abstract: Fifty-one patients undergoing cholecystectomy received a single dose of buprenorphine 4.5-12 μg kg−1 at induction. Median duration of analgesia after surgery was 6 h. Multiple regression analysis showed the duration of analgesia to be slightly dependent on the age of the patient. No relationship was found between the duration of analgesia and the weight-related dose of buprenorphine, the age, sex or body weight of the patient, the duration of anaesthesia, or the dose of droperidol or thiopentone administered.

Comparison of Analgesic Activity of Buprenorphine Hydrochloride and Morphine in Patients with Moderate to Severe Pain Postoperatively

Abstract: Since buprenorphine has been reported to be effectively analgesic yet free of addiction potential, two single-dose, double-blind, parallel studies were conducted to compare its analgesic activity and safety with those of morphine. The patients in each study consisted of patients experiencing moderate to severe postoperative pain. They were treated with an intramuscular injection of either 0.2 or 0.4 milligram of buprenorphine (Study I) or 0.15 or 0.30 milligram of buprenorphine (Study II) compared with 5.0 or 10.0 milligrams of morphine in both instances. Patients were interviewed prior to drug treatment and at 10, 20 and 30 minutes, and one, two, three, four, five and six hours postdose to determine pain intensity and relief. The degree of sedation, vital signs and side effects were evaluated. Buprenorphine generally appeared comparable to morphine in the onset and duration of action and in side effect liability.