Pharmacology of Methamphetamine

Abstract

Methamphetamine increases dopamine levels in the central nervous system (CNS) by as much as 2,600%, primarily by stimulating presynaptic release of the neurotransmitter, rather than by re-uptake blockade [9, 11]. Such increase has the effect of stimulating regions of the brain linked with vigilance and the action of the heart [11]. For a short while, the user feels sharper, stronger and more energetic. It is believed that a significant proportion of the dopamine-producing cells in the brain can be damaged by prolonged exposure to even low levels of methamphetamine, and this is responsible for reduced levels of dopamine; this can affect memory-, attention- and decision-taking functions. Chronic methamphetamine abuse is reported to lead to significant reduction in grey matter in the brain, greater than those in dementia or schizophrenia patients, though this needs further clarification. Associated health risks involve social and family problems, including risky sexual behavior. Drug-induced psychosis may result. Methamphetamine effects last for days in the body, and some degree of neurological impairment may last up to 2 years or more after cessation of the drug [12].