Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pentazocine”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1984

Pharmacological study of pentazocine-naloxone combination: interest as a potentially non abusable oral form of pentazocine.

The hypothesis that co-administration of naloxone would not affect oral but would block parenteral pentazocine's activities was tested in two rat models, the Randall-Selitto and the hypertonic saline writhing tests. A 100:1 dose ratio of pentazocine-naloxone was shown to be optimal and equivalent in oral analgesic effects to pentazocine alone. The same combination, administered parenterally, showed little or no analgesia indicating a suppression of pentazocine activity. Pentazocine-naloxone combination appears, therefore, as a feasible means to retain full analgesic activity of pentazocine when administered orally while any attempt to extract pentazocine from this formulation for intravenous administration would result in little or no pharmacological effect and, therefore, eliminate the potential parenteral abuse of tablets.

Administration, Oral↗
PubMed1983

Comparison of oral pentazocine, oral diazepam and intramuscular pentazocine for paediatric premedication.

Oral pentazocine-atropine, oral diazepam-atropine and IM pentazocine-atropine were compared as preoperative medication in children. Observations in 300 children ages 1-14 years included the emotional state at time of induction of anaesthesia, smoothness of induction, dryness of oral mucosa and tongue, incidence of vomiting, and emotional state and length of stay in the recovery room. The incidence of a calm state at the time of induction and smoothness of induction of anaesthesia was the same following oral and IM premedication. There was satisfactory drying of salivary secretions. The incidence of vomiting in the recovery room was the same following oral and IM premedication. However, children in age groups 1-4 and 5-9 years who received diazepam-atropine were more restless in the recovery room than those who received oral or IM pentazocine-atropine. More children in groups 1-4 and 5-9 years who received IM pentazocine-atropine stayed longer in the recovery room. We conclude that oral diazepam-atropine and oral pentazocine-atropine are comparable as to preoperative medication IM pentazocine-atropine and that they can be given as an alternate to intramuscular injection.

Administration, Oral↗
PubMed1992

[Pharmacokinetics of ketamine and pentazocine during total intravenous anesthesia with droperidol, pentazocine and ketamine].

Pharmacokinetics was studied in ten surgical patients who underwent various operative procedures of about 4 hours under total intravenous anesthesia with droperidol, pentazocine and ketamine (DPK). Plasma levels of ketamine, its metabolites and pentazocine were determined thirteen times during and after DPK. During anesthesia, ketamine (KO) and norketamine (KMI) levels ranged from 0.7 to 1.0 micrograms.ml-1 and from 0.09 to 0.74 micrograms.ml-1, respectively. A small amount of dehydronorketamine (KM II) was detected only 90 min after the start of DPK anesthesia. Plasma half-lives of ketamine were calculated to be 33 min for distribution phase (alpha phase) and 60 min for elimination phase (beta phase), respectively. Pentazocine levels decreased 300 min after the induction of DPK to 10% of the control level measured 5 min after its injection. Plasma half-lives of pentazocine were 60 min for alpha phase and 140 min for beta phase, respectively. The data obtained in this clinical study show that pharmacokinetics of ketamine during DPK is almost similar to that of DFK.

Adolescent↗
PubMed1980

Pentazocine-induced neuromuscular syndrome: clinical, histochemical features in two cases and a tissue culture study of pentazocine-block myogenesis in human foetal muscle.

Two cases of pentazocine-induced neuromuscular syndrome in addicted patients are reported. Histochemical and histographic analysis of muscle biopsies performed in areas distant from the site of injection, disclosed type II muscle fibre atrophy. In order to clarify the pentazocine myotoxic mechanism, a tissue culture study was performed and the effects of the drug on the extent of myogenesis in human foetal muscle cultures were assayed. The tissue culture studies showed: 1 a complete block of myogenesis in pentazocine-treated human foetal muscle cultures and 2. a delayed fusion process when the pentazocine-treated cultures were pretreated with 10(-5) M D-arabinofuranosylcytosine (ara-C). In conclusion it is suggested that the overgrowth of fibroblasts, supported by tissue culture study, in tissues other than muscle (i.e. nerve) could explain the neurogenic aspects found in these patients.

Adult↗
PubMed1988

Pentazocine-naloxone experimenters among abusers of pentazocine and tripelennamine from a VA treatment population.

Psychiatric diagnostic profiles, drug and personal histories, and social support measures were obtained for a clinic sample of abusers of pentazocine when the drug was withdrawn and re-released by the manufacturer compounded with the opiate antagonist naloxone. Nearly 50% of the sample (N = 99) reported using the new drug during the following 6 to 9 months, despite its reduced abuse potential. Reinterviews revealed that claimed use of pentazocine dropped to half.

Adult↗
PubMed1977

Pentazocine suppositories for post-operative pain: intramuscular pentazocine injections versus suppositories in a controlled trial in 588 patients.

A between-patient comparison of the analgesic effect of pentazocine 50 mg by suppository and 30--45 mg by intramuscular injection was made in 558 postoperative patients, 54% within 24 hours of operation. The suppositories proved acceptable overall, even though effectiveness was less at half an hour after administration (particularly in those patients with severe initial pain) and there was greater need for further analgesia at one hour. The cost of treatment with suppositories is less than with injections. After the suppositories there were half as many patients asleep at one hour than after injections, and fewer possible side-effects (7 compared to 24).

Adolescent↗
PubMed1986

Stereospecific effects of d- and l-pentazocine on contractions of the mouse vas deferens.

The effects of the d- and l-isomers of pentazocine were compared to that of racemic pentazocine on contractions of the mouse isolated vas deferens. L-pentazocine inhibited electrically evoked contractions of the mouse vas deferens (MVD) in a dose-dependent manner (ID50 0.37 +/- 0.04 microM). In contrast, d-pentazocine augmented field stimulated contractions dose-dependently; per cent increases in contractions at 10 and 30 microM were 57.8 +/- 18.0 and 98.0 +/- 15.1%, respectively. Racemic pentazocine produced an intermediate effect between the two isomers. The effect of 1-pentazocine was antagonized by naloxone, whereas that of d-pentazocine was not. L-pentazocine did not effect the response of the MVD to exogenous norepinephrine at any concentration tested, while d-pentazocine depressed the response of the MVD to exogenous norepinephrine at one dose (0.3 microM). These findings demonstrate that d- and l-pentazocine produce opposite effects on the MVD. The effects of l-pentazocine are opioid mediated, while those of d-pentazocine are not. In the racemic mixture the opposing effects of the two isomers modulate each other, resulting in a diminished effect.

Animals↗
PubMed1982

Effects of the combination of tripelennamine and pentazocine at the behavioral and molecular levels.

The purpose of the present experiments was to determine if the antihistamine tripelennamine potentiates the morphine-like effects of the narcotic-antagonist analgesic pentazocine at the behavioral level or the molecular level or both. At the behavioral level, the effects of pentazocine were determined alone and in combination with tripelennamine in rats trained to discriminate between saline and either morphine or the psychotomimetic narcotic derivative SKF 10,047. The interaction between pentazocine and tripelennamine were also evaluated in the guinea-pig ileum preparation and in the [3H]-naloxone opiate receptor binding assay. Tripelennamine significantly enhanced the morphine-like discriminative stimulus effects of pentazocine and markedly reduced the SKF 10,047-like stimulus effects of pentazocine. Naloxone antagonized the morphine-like effects of pentazocine plus tripelennamine. Pentazocine significantly constricted pupils in the rat, an effect which was additive with the mydriatic effects of tripelennamine. Inhibition of the twitch-height of the electrically stimulated guinea-pig ileum by pentazocine was not affected by tripelennamine. Further, tripelennamine did not modify the Ke for naloxone in antagonizing pentazocine. Inhibition of specific [3H]-naloxone binding by pentazocine was also not affected by tripelennamine. These results are consistent with the hypothesis that the potentiation of the morphine-like effects of pentazocine by tripelennamine which was observed behaviorally was not due to molecular interactions at the morphine receptor. At least a part of this interaction may be attributable to tripelennamine decreasing the psychotomimetic actions of pentazocine.

Animals↗
PubMed1996

Dissociation of the motor effects of (+)-pentazocine from binding to sigma 1 sites.

Radioligand binding and behavioral studies were conducted to determine whether a relationship existed between the motor effects produced by (+)-pentazocine and its binding to sigma sites. Scatchard analyses revealed decreased [3H](+)-pentazocine binding in middle aged rats (5-6 months old) compared to young adult rats (2-3 months old). However, there was no difference between the extent of circling behavior or dystonia produced by microinjection of (+)-pentazocine into the substantia nigra or red nucleus in the older animals compared to the young adult rats. There was also a significant decrease in [3H](+)-pentazocine binding in rats chronically treated with haloperidol. Again, however, despite the reduction in [3H](+)-pentazocine binding, there was no difference between the extent of dystonia produced by unilateral intrarubral microinjection of (+)-pentazocine into animals chronically treated with haloperidol vs. saline. The postural changes produced by (+)-pentazocine could not be attenuated with coadministration of the putative sigma receptor antagonist BD1047 (N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(dimethylamino) ethylamine), or the opiate receptor antagonist naloxone. However, the (+)-opiate, (+)-nordihydrocodeinone, partially attenuated the postural effects of (+)-pentazocine, despite its very low affinity for sigma 1, sigma 2, or opiate receptors. Taken together with previous studies, the results suggest that [3H](+)-pentazocine is a potent and selective probe for sigma 1 binding sites, but the in vivo effects of (+)-pentazocine cannot be fully attributed to actions through these sites. Some of the in vivo effects of (+)-pentazocine appear to involve other binding sites that are not detected under the conditions normally used in in vitro assays.

Aging↗
PubMed1984

Agonist-antagonistic interactions of pentazocine with morphine studied in mice.

Interactions between the antinociceptive effects of pentazocine and morphine were studied in mice. In the tail-pressure test, the antinociceptive effect of pentazocine, 4.75 to 9.5 mg/kg, SC, was synergistic to that of morphine, 0.69 to 1.38 mg/kg, SC. In the acetic acid writhing test, the effect was also synergistic with pentazocine, 7.13 to 9.5 mg/kg, SC, and morphine, 1.03 to 1.38 mg/kg, SC. In the tail-pinch test, larger doses of morphine than those above were required to suppress the nociceptive response, and simultaneous administration of pentazocine, 2.38 to 19.0 mg/kg, SC, and morphine, 2.75 mg/kg, SC, produced antagonistic effects. Pentazocine, 19.0 mg/kg, completely antagonized the effect of morphine, 2.75 mg/kg, with simultaneous administration at these doses always nearly equipotent to administration of pentazocine alone. These results suggested that when pentazocine and morphine are simultaneously administered, pentazocine synergizes or antagonizes to antinociceptive effects of morphine depending on the dose sizes of morphine and pentazocine, and that the relative saturation levels of morphine and pentazocine at the receptor may be important factors in determining whether the interaction of pentazocine with morphine is antagonistic or synergistic.

Animals↗
PubMed2005

Improvement of memory impairment by (+)- and (-)-pentazocine via sigma, but not kappa opioid receptors.

(+/-)-Pentazocine is widely used clinically to treat mild to moderate pain as a racemic compound. Although it is known that (-)-pentazocine acts as a kappa opioid receptor agonist to exhibit analgesic actions and (+)-pentazocine acts as a sigma receptor agonist without analgesic effects, their combined effect on memory has not been investigated in detail. In this study, the effect of (+)- and/or (-)-pentazocine on scopolamine-induced memory impairment in mice was investigated using spontaneous alternation performance in a Y-maze. (+)-Pentazocine (0.35 micromol/kg, s.c.) administered 30 min before behavioral testing significantly improved the impairment of spontaneous alternation induced by scopolamine. A higher dose of (-)-pentazocine (3.50 micromol/kg, s.c.) also reversed the scopolamine-induced impairment of alternation performance. Interestingly, the ameliorating effects of not only (+)-pentazocine, but also (-)-pentazocine were antagonized by a selective sigma receptor antagonist, N,N-dipropyl-2-[4-methoxy-3-(2-phenylenoxy)-phenyl]-ethylamine monohydrochloride (NE-100) (2.6 micromol/kg, i.p.). However, those effects were not antagonized by a selective kappa opioid receptor antagonist, nor-binaltorphimine (4.9 nmol/mouse, i.c.v.). Coadministration of (+)- and (-)-pentazocine (0.35 or 3.50 micromol/kg each) did not have any additive or antagonizing effects on the percent alternation. An antinociceptive effect was observed only with (-)-pentazocine (3.50 micromol/kg, s.c.), and was antagonized by nor-binaltorphimine (4.9 nmol/mouse, i.c.v.), but not by NE-100 (2.6 micromol/kg, i.p.). These results suggest that although the analgesic effect of pentazocine was mediated via kappa opioid receptors, the ameliorating effect on scopolamine-induced impairment of spontaneous alternation was mediated via sigma receptors, not via kappa opioid receptors.

Acetic Acid↗
PubMed2003

Cardiovascular effects of intravenous pentazocine and cyclazocine in conscious, curarized-conscious, and anesthetized dogs.

The cardiovascular effects of intravenous pentazocine and cyclazocine in dogs were studied under conscious, curarized-conscious (paralyzed by gallamine), and anesthetized states. In the conscious state, blood pressure and heart rate were dose-dependently increased by pentazocine (1, 2, 3 mg/kg) and to a lesser extent by cyclazocine (0.3 mg/kg). In all subsequent experiments on dogs, the results were obtained using 3 mg/kg pentazocine and 0.3 mg/kg cyclazocine. Pentazocine accelerated breathing, peaking at about 10 min, whereas cyclazocine reduced breathing to a minimum in 1 min, followed by a gradual recovery thereafter. In the curarized-conscious state, the blood pressure response to pentazocine was biphasic, namely an initial decrease followed by an increase; chronotrophic activity was stimulated. Pretreatment with either ganglionic or alpha andrenergic blocking agents not only significantly antagonized the pressory responses to the drug but also potentiated the initial decreases in blood pressure and unmasked a bradycardic component, but these parameters were not altered by 0.3 mg/kg naxalone. In open-chest anesthetized dogs, blood pressure, heart rate, contractility, and mean peripheral vascular resistance were simultaneously decreased by both pentazocine and cyclazocine, initially accompanied by increases in aortic blood flow. During the later stages of drug action, only the blood pressure and contractility were increased above control levels (biphasic effect). A comparison of blood pressure and heart rate responses to pentazocine in dogs kept under differing experimental conditions revealed that conscious dogs were more sensitive than curarized conscious and anesthetized animals to pentazocine action. In isolated guinea pig atria, the effect of adrenaline (0.1, 0.3, or 1 mg/mL) on the spontaneous breathing rate was significantly augmented by 10 mg/mL pentazocine (p < 0.02 for 0.3 g/mL; p < 0.01 for 0.1 g/mL adrenaline). In dogs, however, adrenaline (1 mg/kg)-induced increases in heart contractility, aortic blood flow, and blood pressure remained almost unaltered in the presence of pentazocine. We concluded that the abovementioned cardiovascular responses to pentazocine and cyclazocine are a consequence of the sum of the two following opposing effects: (i) an indirect reflex activation of sympathetic neuromediation in the periphery, and (ii) a direct membrane effect on the heart leading to bradycardia and a depression in myocardial contractility.

Anesthesia↗