Naloxone abstinence syndrome

MaUn DH, Lake JR, Carter VA, Cunningham JS, Wilson OB (1993) Naloxone precipitates nicotine abstinence syndrome in the rat. Psychopharmacology 112(2-3) 339-342 MaUn DH, Lake JR, Carter VA, Cunningham JS, Hebert JS, Conrad DL, Wilson OB (1994) The nicotinic antagonist mecamylamine precipitates nicotine abstinence syndrome. Psychopharmacology 115 339-342... 

Malin DH, Lake JR, Carter VA, Cunningham JS, Wilson OB (1993a) Naloxone precipitates nicotine abstinence syndrome in the rat. Psychopharmacology 112 339-342... 

When given intravenously to a morphine-treated subject, the antagonist completely and dramatically reverses the opioid effects within 1-3 minutes. In individuals who are acutely depressed by an overdose of an opioid, the antagonist effectively normalizes respiration, level of consciousness, pupil size, bowel activity, and awareness of pain. In dependent subjects who appear normal while taking opioids, naloxone or naltrexone almost instantaneously precipitates an abstinence syndrome. 

Naloxone Antagonist at P-, 5, and receptors Rapidly antagonizes all opioid effects Opioid overdose Duration 1-2 h (may have to be repeated when treating overdose) Toxicity Precipitates abstinence syndrome in dependent users... 

The opioid antagonist naloxone reverses the effects of a dose of morphine or heroin within minutes. This may be life-saving in the case of a massive overdose (see Chapters 31 and 59). Naloxone administration also provokes an acute withdrawal (precipitated abstinence) syndrome in a dependent person who has recently taken an opioid. 

Naloxone Nonselective antagonist of opioid receptors Reverses the acute effects of opioids can precipitate severe abstinence syndrome Opioid overdose Effect much shorter than morphine (1-2 h), therefore several injections required... 

Morphine- dependent rats Morphine M-Con.-GVIA two M. pellets (75mg each) implanted s.c. for 72 h -C. 20 ng/rat i.c.v. oj-C injected in M dependent rats 15 min before naloxone challenge (2 mg/kg i.p.) signif. attenuated the abstinence syndrome Basilico et al. (1992)... 

Baeyens, J.M., Esposito, E., Ossowska, G., Samanin, R. Effects of peripheral and central administration of calcium channel blockers in the naloxone-precipitated abstinence syndrome in morphine-dependent rats, Eur. J. Pharmacol. 1987, 137, 9-13. 

Naloxone (Narcan) and naltrexone hydrochloride (Trexan) reverse the respiratory depressant action of narcotics related to morphine, meperidine, and methadone. They differ from other narcotic analgesics in several respects. Naloxone does not cause respiratory depression, pupillary constriction, sedation, or analgesia. However, it does antagonize the actions of pentazocine. Naloxone neither antagonizes the respiratory depressant effects of barbiturates and other hypnotics nor aggravates their depressant effects on respiration. Similar to nalorphine, naloxone precipitates an abstinence syndrome when administered to patients addicted to opiate-like drugs. 

In 1915, it was shown that N-allylnorcodeine abolished both heroine- and morphine-indueed respiratory depression. Almost 25 years later (1940), it was observed that N-allylnormorphine (eom-monly known as nalorphine) possessed more marked and signifieant morphine antagonizing aetions. Thirteen years later (1953), it was demonstrated that nalorphine had the ability to arrest severe abstinence syndromes in postaddicts who were earlier treated briefly with either morphine, methadone or heroine. Examples of narcotic antagonists include nalorphine hydrochloride naloxone hydrochloride propiram fnmarate and pentazocine. 

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