Opioid withdrawal syndrome

A protracted abstinence syndrome may follow the acute opioid withdrawal syndrome and last for many weeks (Martin et al. 1973). In one study ofher-oin addicts detoxified with methadone, withdrawal distress peaked at day 20,... 

Severe opioid withdrawal syndromes Severe opioid withdrawal syndromes precipitated by accidental naltrexone ingestion have occurred in opioid-dependent individuals. Withdrawal symptoms usually appear within 5 minutes or less of ingestion and may last up to 48 hours. 

Davies AN, Bond C. Transdermal fentanyl and the opioid withdrawal syndrome. Palliat Med 1996 10(4) 348. 

Sun HL. Naloxone-precipitated acute opioid withdrawal syndrome after epidural morphine. Anesth Analg 1998 86(3) 544-5. 

Eriator II, Sun HL. Naloxone acute opioid withdrawal syndrome or side effects Anesth Analg 1998 87(5) 1214. 

The role of opioid antagonists in the treatment of pruritus in cholestatic liver disease has been reviewed (5). Their use is based on the theory that implicates opioid neurotransmission as the cause of itching in this condition, and it has been observed that opioid antagonists, while providing relief from itching in patients with cholestasis, also cause symptoms similar to those seen in the opioid withdrawal syndrome. It has therefore been suggested that... 

Headache occurred in two children, and an opioid withdrawal syndrome occurred in one child during the first... 

One of the limitations of clonidine treatment is that it does not appear to reduce the duration of the opioid withdrawal syndrome. In one study, 10 days of clonidine therapy were required to suppress the symptoms of opioid withdrawal from long-acting opioids such as methadone (70). 

Talwin mixed with blue-colored pyribenzamine tablets). Since pentazocine can produce dependency, abrupt cessation may precipitate the opioid withdrawal syndrome. Chronic intramuscular pentazocine injections have been associated with fibrous myopathy and localized neuropathy. 

Tolerance and dependence may occur with prolonged use. Abrupt cessation in patients utilizing propoxyphene chronically may result in an opioid withdrawal syndrome in both adults and neonates. 

Dehpour AR, Samini M, Arad MA, Namiranian K. Clonidine attenuates naloxone-induced opioid-withdrawal syndrome in cholestatic mice. Pharmacol Toxicol 2001 89 129-132. 

F. Opioid withdrawal syndrome can cause anxiety, piioerection (goose-bumps), abdominai cramps and diarrhea, and insomnia. 

A patient taking lamivudine and zidovudine had a marked decrease in methadone serum levels when ritonavir was added." Another patient receiving methadone experienced an opioid withdrawal syndrome when ritonavir was added to a similar antiretroviral regimen. ... 

The abrupt cessation of a repeatedly or continuously administered opioid agonist, or the administration of an antagonist typically results in the withdrawal syndrome. Signs and symptoms include sweating, tachycardia, hypertension, diarrhea, hyperventilation, and hyperre-flexia. 

Personality variables, state of mind at time of withdrawal, and expectations of severity of symptoms all may affect withdrawal severity (Kleber 1981). One study found that merely providing addicts information about the withdrawal syndrome resulted in lower levels of withdrawal symptoms (Green and Gos-sop 1988). Naloxone rapidly induces a severe withdrawal syndrome, which peaks within 30 minutes and then declines rapidly. Until the antagonist is eliminated, only partial suppression of the withdrawal syndrome is possible, and then only by using very high opioid doses, which may cause respiratory depression when naloxone is metabolized. 

The answer is c. (Hardman, p 546.) Pentazocine is a mixed agonist-antagonist of opioid receptors. When a partial agonist, such as pentazocine, displaces a full agonist, such as methadone, the receptor is less activated this leads to withdrawal syndrome in an opioid-dependent person. 

The answer is c. (Hardman, pp 574—575.) Phencyclidine is a hallucinogenic compound with no opioid activity Its mechanism of action is amphetamine-like. A withdrawal syndrome has not been described for this drug in human subjects. In overdose, the treatment of choice for the psychotic activity is the antipsychotic drug haloperidol. 

Opioids also interact with excitatory amino acid neurotransmitters. At lower micromolar concentrations, p agonists (e.g., DAMGO) enhance NMDA activity in the nucleus accumbens, but inhibit non-NMDA activity (Martin et al. 1997). At higher concentrations (5 pM), NMDA currents are reduced. Conversely, central administration of glutamate can precipitate a withdrawal syndrome in morphine-dependent animals, similar to the opioid antagonist naloxone. NMDA mechanisms also appear to be involved in the development of morphine tolerance. Competitive and noncompetitive NMDA antagonists and inhibitors of nitric oxide synthase reduce or eliminate tolerance to morphine (Elliott et al. 1995 Bilsky et al. 1996). However, this does not occur for tolerance to k opioids. Pharmacokinetics... 

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