Amphetamines dependence

The development of effective pharmacotherapy has lagged behind progress in understanding the reward mechanisms and chronic impairments underlying stimulant abuse. Pharmacological and behavioral treatment approaches that have been used for cocaine abuse have not been as widely tested for the treatment of amphetamine abuse, limiting what can be offered for treatment of this disorder. No treatment agents are approved by the FDA for treatment of cocaine or amphetamine dependence. 

More than 40 medications have been investigated but none have shown consistent efficacy for primary cocaine or amphetamine dependence. These medications include dopaminergic agonists, antidepressants, and more recently disulfiram, selegiline, and a cocaine vaccine (see Table 5—2 for summary). Studies have been relatively brief and have focused on abstinence initiation rather than on relapse prevention, but even these modest treatment goals have not been attained. The focus in the discussion that follows is on pharmacotherapies for cocaine dependence, because very few clinical trials have been completed with amphetamine-dependent patients. Furthermore, none of the studies of amphetamine dependence have shown results different from those described for cocaine dependence (Rawson et al. 2002b Srisurapanont et al. 2001). 

Srisurapanont M, Jarusuraisin N, Kittirattanapaiboon P Treatment for amphetamine dependence and abuse. Cochrane Database Syst Rev 4 CD003022, 2001 Srisurapanont M, Ali R, Marsden J, et al Psychotic symptoms in methamphetamine psychotic in-patients. Int J Neuropsychopharmacol 6 347-352, 2003 Substance Abuse and Mental Health Services Administration Overview of Findings From the 2002 National Survey on Drug Use and Health (DHHS Publ No SMA 03-3774). Rockville, MD, Substance Abuse and Mental Health Services Administration, 2003... 

There are no proven pharmacotherapies for treatment of cocaine or amphetamine dependence. Disulfiram, however, shows some promise in randomized controlled trials for treating cocaine dependence at doses of 250 mg daily, especially in combination with CBT.45 Its mechanism of action for treating cocaine dependence is not known, but may be due to its inhibition of the dopamine P-hydroxylase enzyme that converts DA to NE in the brain. The resulting increase in DA levels may counter the DA-deficient state that is believed to underlie cocaine withdrawal and craving. 

Cantwell, B., McBride, AJ. Self-detoxification by amphetamine-dependent patients a pilot study. Drug Alcohol Depend. 49 157, 1998. 

Alcohol Abuse, Alcohol Dependence Amphetamine Abuse, Amphetamine Dependence Cannabis Abuse, Cannabis Dependence Cocaine Abuse, Cocaine Dependence Hallucinogen Abuse, Hallucinogen Dependence Inhalant Abuse, Inhalant Dependence Nicotine Dependence Opiate Abuse, Opiate Dependence Phencyclidine Abuse, Phencyclidine Dependence... 

Carnwath T, Gabbay M Barnard f (2000). A share of the action general practitioner involvement in drug misuse treatment in Greater Manchester. Drugs Education, Prevention and Policy, 7, 235-44 Carnwath T, Garvey T Holland M (2002). The prescription of dexamphetamine to patients with schizophrenia and amphetamine dependence. Journal of Psychopharmacology, 16, 372-7... 

Merrill J, McBride A, Pates R, Peters L, Tetlow A, Roberts C, Arnold K, Crean J, Lomax S Deakin B (2005). Dexamphetamine substitution as a treatment of amphetamine dependence a two-centre randomized controlled trial. Drugs Education, Prevention Policy, 12, 94-97... 

Poison RG, Fleming PM O Shea JK (1993). Fluoxetine in the treatment of amphetamine dependence. Human Psychopharmacology, 8, 55-8... 

Amphetamine is metabolized by deamination, oxidation, and hydroxylation. Figure 4.1 illustrates the metabolic scheme for amphetamine. Deamination produces an inactive metabolite, phe-nylacetone, which is further oxidized to benzoic acid and then excreted in urine as hippuric acid and glucuronide conjugates. In addition, amphetamine is also converted to norephedrine by oxidation and then this metabolite and the parent compound are / -hydroxylated. Several metabolites, including norephedrine, its hydroxy metabolite, and hydroxy amphetamine, are pharmacologically active. The excretion of amphetamine depends on urinary pH. In healthy men who were administered 5 mg of isotopically labeled d,l-amphetamine, approximately 90% of the dose was excreted... 

Animal studies show that amphetamine abuse may cause birth defects. There are no controlled studies of this effect in humans however it is known that pregnant women who are amphetamine-dependent may give birth prematurely and are more likely to have infants with a low birth weight. Amphetamines cross the placenta, so a baby bom to an amphetamine abuser may experience withdrawal symptoms once the drug begins to leave the infant s system. 

Treatment for amphetamine dependence may be either inpatient or outpatient. Inpatient, or residential, drug programs require a patient to live at the hospital or rehab facility for a period of several weeks to several months. Outpatient programs allow patients to spend part of their day at the treatment facility, and return home at night. 

Choreoathetoid movements have been evaluated in samples of cocaine-dependent men (n = 71), amphetamine-dependent men (n = 9), and 56 controls (137). The cocaine-dependent men had significantly worse non-facial (limbs plus body) choreoathetosis scores, and the differences between groups were most marked in the younger age groups. The facial scores were increased only in those under 32 years of age, as they were in the younger amphetamine-dependent subjects. The authors suggested that the absence of choreoathetoid movements in the older cocaine-dependent men may represent an age-related self-selection effect. 

There is no truth to these stories, but both MDA and MDMA can cause bad reactions at high doses. Some people snort them or (rarely) inject them intravenously, intensifying their action and potential for harm. Combining these drugs with alcohol or other depressants also increases the possibility of adverse effects. As sexual drugs, hoth compounds may enhance the pleasure of touching, but they interfere with erection in men and with orgasm in both men and w omen, A few cases of dependence on MDMA have been reported they resemble cases of amphetamine dependence. 

Srisurapanont M, jarusuraisin N, Kittirattanapaiboon P. Treatment for amphetamine dependence and abuse. Cochrane Database Syst Rev. 2001 (4) CD003022. 

Jonsson L-E. Pharmacological blockade of amphetamine effects in amphetamine dependent subjects. Eur J Clin Pharmacol (1912) 4, 206-11,... 

Longo M, Wickes W, Smout M, Harrison S, Cahill S, White JM. Randomized controlled trial of dexamphetamine maintenance for the treatment of meth-amphetamine dependence. Addiction 2010 105(1) 146-54. 

Karila L, Weinstein A, Aubin H-J, Benyamina A, Reynaud M, Batki SL. Pharmacological approaches to meth-amphetamine dependence a focused review. Br J Clin Pharmacol 2010 69 578-92. 

Jayaram-Lindstrom N, Hammarberg A, Beck O, Franck J. Naltrexone tor the treatment of amphetamine dependence a randomized, placebo-controlled trial. Am J Psychiatry 2008 165(11) 1442-8. 

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