The discriminative stimulus effects of acute morphine followed by naltrexone have been described previously in nonhuman primates. The purposes of this study were to 1) extend the pharmacological characterization of the discrimination by testing mu-opioid agonists other than morphine and opioid-like compounds other than naltrexone and 2) to examine further the relationship between agonist pretre...

Naltrexone/bupropion is an investigational combination for weight loss and maintenance in patients who are obese or have a BMI ≥ 27 kg/m(2) with comorbid diabetes, hypertension or hyperlipidemia. Pooled results from four phase 3 trials reveal placebo-subtracted mean weight loss of 4.7% (range 3.2-5.2%) with naltrexone/bupropion after 1 year (p < 0.001 vs. placebo in each trial). The placebo-sub...

PURPOSE: Opioid dependence (OD) is a serious and growing clinical condition with increasing social costs that requires expanding treatment beyond opioid agonist substitution. The opioid antagonist naltrexone has displayed a remarkable association of theoretical effectiveness and poor clinical utility in treating OD due to noncompliant behavior and low acceptability among patients, only partly m...

Extracellular and intracellular microelectrode studies were conducted to test the actions and interactions of naloxone and naltrexone, two supposedly "pure" opiate antagonists. Both were shown to depress excitability and action potential production when applied in relatively high concentrations. Low naltrexone concentrations antagonized the depression produced by naloxone, but low naloxone conc...

BACKGROUND Endogenous opiates may affect various aspects of reproductive and metabolic function in patients with polycystic ovary syndrome (PCOS). This study evaluated long-term inhibition of the opioid system using naltrexone in clomiphene citrate (CC)-resistant women with PCOS. METHODS A group of 30 infertile females with PCOS were evaluated; all subjects were obese, hyperandrogenic and hyp...

BACKGROUND & AIMS The efficacy of currently available therapeutic agents for cholestatic pruritus is often disappointing. The aim of this study was to assess the antipruritic effect of naltrexone, an oral opiate receptor antagonist. METHODS Sixteen patients with pruritus of chronic cholestasis were randomized to receive naltrexone (4-week course of 50 mg naltrexone daily) or placebo. Pruritus...

Naltrexone and acamprosate are the most effective drugs in reducing alcohol consumption, operating through different pharmacological mechanisms. Some studies have demonstrated that naltrexone and acamprosate in combination have significantly greater effectiveness in alcohol therapy than either agent used alone. We have previously found that beta-endorphin plasma levels are increased after repea...

BACKGROUND Morphine sulfate and naltrexone hydrochloride extended-release capsules (EMBEDA, King Pharmaceuticals, Inc., Bristol, TN), indicated for management of chronic, moderate-to-severe pain, contain pellets of extended-release morphine sulfate with a sequestered naltrexone core (MS-sNT). Taken as directed, morphine provides analgesia while naltrexone remains sequestered; if tampered with b...

Treatment outcomes were compared for 2 groups of subjects detoxified from methadone using clonidine. One group of 12 subjects was encouraged to continue in treatment with naltrexone, while the other 12 subjects did not have naltrexone treatment available. Results suggested that those subjects who had naltrexone available were more successful at completing the 10 day detoxification treatment and...

AIMS To analyse the possible associations between sweet preference and the efficacy of naltrexone treatment of alcohol dependence. METHODS The preference for different concentrations of sucrose was evaluated in 78 participants diagnosed with alcohol dependence after treatment for 32 weeks with naltrexone or placebo without prior detoxification. RESULTS A significant difference between naltr...