Heroin effects

Naltrexone, nalmefene Like naloxone but longer durations of action (10+ h) naltrexone is used in maintenance programs and can block heroin effects for up to 48 h ... 

P-Endorphin. A peptide corresponding to the 31 C-terminal amino acids of P-LPH was first discovered in camel pituitary tissue (10). This substance is P-endorphin, which exerts a potent analgesic effect by binding to cell surface receptors in the central nervous system. The sequence of P-endorphin is well conserved across species for the first 25 N-terminal amino acids. Opiates derived from plant sources, eg, heroin, morphine, opium, etc, exert their actions by interacting with the P-endorphin receptor. On a molar basis, this peptide has approximately five times the potency of morphine. Both P-endorphin and ACTH ate cosecreted from the pituitary gland. Whereas the physiologic importance of P-endorphin release into the systemic circulation is not certain, this molecule clearly has been shown to be an important neurotransmitter within the central nervous system. Endorphin has been invaluable as a research tool, but has not been clinically useful due to the avadabihty of plant-derived opiates. 

The nurse should teach the patient taking naltrexone the impact of therapy. While taking the drug, any use of heroin or other opiate by the patient results in no effect. In fact, large doses of heroin or other opiates can overcome the drug s effect and result in coma or death. 

Jerry Jbnes is to begin receiving methadone for the treatment of heroin dependency, tkrry asks why methadone, a narcotic, is effective in the treatment of narcotic dependency. How wouldyou explain this to the patient What information would be important to give this patient while he is in the methadone program ... 

Opioids are easily absorbed subcutaneously and intramuscularly, as well as from the gastrointestinal tract, nasal mucosa (e.g., when heroin is used as snuff), and lung (e.g., when opium is smoked). About 90% of the excretion of morphine occurs during the first 24 hours, but traces are detectable in urine for more than 48 hours. Heroin (diacetyhnorphine) is hydrolyzed to monoacetylmorphine, which is then hydrolyzed to morphine. Morphine and monoacetylmorphine are responsible for the pharmacologic effects of heroin. Heroin produces effects more rapidly than morphine because it is more lipid soluble and therefore crosses the blood-brain barrier faster. In the urine, heroin is detected as free morphine and morphine glucuronide (Gutstein and Akil 2001 Jaffe et al. 2004). 

At the doses used, there is blockage of the effects of as much as 25 mg of injected heroin. Toxicity in heroin addicts is low, but some reported subtle adverse effects of naltrexone such as decreased energy (Hollister et al. 1981). Nonaddicted obese subjects have been known to develop markedly elevated transaminase levels at doses of 300 mg/day (Mitchell et al. 1987). The inference has been drawn that high doses are potentially hepatotoxic (Pfohl et al. 1986), and the drug is contraindicated in liver failure or acute hepatitis. 

Potenza MN, Gold SJ, Roby-Shcmkowitz A, et al Effects of regulators of G protein-signaling proteins on the functional response of the mu-opioid receptor in a mel-anophore-based assay. J Pharmacol Exp Ther 291 482 91, 1999 Quaglio G, Talamini G, Lechi A, et al Study of 2708 heroin-related deaths in northeastern Italy 1985—98 to establish the main causes of death. Addiction 96 1127— 1137, 2001... 

Seecof R, Tennant FS Subjective perceptions to the intravenous rush of heroin and cocaine in opioid addicts. Am J Drug Alcohol Abuse 12 79—87, 1987 Sees KL, Delucci KL, Masson C, et al Methadone maintenance vs. 180-day psycho-socially enriched detoxification for treatment of opioid dependence a randomized controlled trial. JAMA 283 1303-1310, 2000 Sells SB Treatment effectiveness, in Handbook on Drug Abuse. Edited by Dupont RE, Goldstein A, O Donnell J. Washington, DC, U.S. Government Printing Office, 1979, pp 105-118... 

Walker BM, Ettenberg A The effects of alprazolam on conditioned place preferences produced by intravenous heroin. Pharmacol Biochem Behav 75 75 80, 2003 Weens EM, Griffiths RR Zolpidem self-injection with concurrent physical dependence under conditions of long-term continuous availability in baboons. Behav Pharmacol 9 285—297, 1998... 

Toluene, volatile nitrites, and anesthetics, like other substances of abuse such as cocaine, nicotine, and heroin, are characterized by rapid absorption, rapid entry into the brain, high bioavailability, a short half-life, and a rapid rate of metabolism and clearance (Gerasimov et al. 2002 Pontieri et al. 1996, 1998). Because these pharmacokinetic parameters are associated with the ability of addictive substances to induce positive reinforcing effects, it appears that the pharmacokinetic features of inhalants contribute to their high abuse liability among susceptible individuals. 

Kosten T, Poling J, Oliveto A Effects of reducing contingency management values on heroin and cocaine use for buprenorphine- and desipramine-treated patients. Addiction 98 665-671, 2003b... 

Methadone long duration and orally effective, thereby useful in weaning off heroin. 

The sudden influx of smokable heroin in the 1980s caused a dramatic increase in use, because it was no longer necessary to inject the drug in order to obtain its effects. Despite new initiatives to try to reduce heroin use it has continued to increase and there is concern about the wider availability and use of cheap heroin among young people, particularly in deprived areas. 

Griffiths, RR. Wurster, R.M. and Brady, J.V. Discrete-trial choiee proeedure Effects of naloxone and methadone on choice between food and heroin. Pharmacol Rev 27 357-365. 1975. 

The higher than expected frequency of alcohol PCP -, and heroin PCP-rel ated deaths may be the result of an interaction of the combined substances. Balster (this volume) anticipated an interaction of the combined substances when he reported "PCP very markedly enhances the effects of classical depressant drugs, including barbiturates and ethanol."... 

The higher than expected frequencies of alcohol PCP - and heroin PCP-related deaths also would have occurred if the combinations were preferred by the users. The motivation may involve the injection of heroin to moderate the adverse effects of PCP, or the use of PCP to ease the pain of heroin withdrawal. Another explanation assumes a stimulant effect of PCP. The use of stimulants, especially cocaine, with heroin is increasingly popular among heroin users (Kozel et al. 1982). 

The number of alcohol PCP - and heroin PCP-related deaths was higher than expected. Users may prefer taking these drugs in combination, or there may be an interaction in the effect of the combinations. Many of the PCP-related deaths are the consequence of some external event rather than a direct consequence of the drug itself. 

The effects of PCP, heroin, and methadone upon the developing fetus may indeed be different. We have found that the PCP infants are more deviant in their development than the reported development of the heroin and methadone infants. Our concerns about stating that drug use by the mothers during pregnancy does not affect developmental outcome are great. 

Swerdlow N. R., Vaccarino F. J., Koob G. F. (1985). Effects of naloxone on heroin-, amphetamine- and caffeine-stimulated locomotor activity in the rat. Pharmacol. Biochem. Behav. 23, 499-501. 

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