Methamphetamine is a psychostimulant of the phenethylamine and amphetamine class of drugs. It increases alertness, concentration, energy, and in high doses, can induce euphoria, enhance self-esteem, and increase libido. Methamphetamine has high potential for abuse and addiction by activating the psychological reward system via triggering a cascading release of dopamine, norepinephrine and serotonin in the brain.