A methamphetamine addict (see also "tweeker".) Methamphetamine addiction is usually a hopeless condition, in that chronic abuse of the drug causes irrepairable brain and central nervous system damage, the former leading to lack of impulse control, extreme paranoia, extreme lack of empathy and reasoning power. This is due to the drug's destruction of the limbic system in the brain, a condition which seldom is reversible. Most such addicts are extremely paranoid, exhibit flagrant dishonesty and are criminals in one way or another. Most methheads exhibit single-minded behavior (being "stuck"), usually devoted solely to getting their drug of choice, and will commit crimes against loved ones as easily as against strangers. Self-loathing causes serious self-destructive behavior. Lack of sleep, poor nutrition and poor hygiene ages all methheads far beyond their years and life expectancy is short, usually caused by brain, renal and liver damage. Also a hallmark of the addict is severe cystic acne and rotted teeth. Once a methhead starts "slamming" their drug (using hypodermic syringes, usually .5 ml insulin types) they are generally hopeless, and even with long term rehabilitation, will relapse as bad as before or worse. Sex drive among females becomes nil with heavy use, and they use sex as a weapon, lure or means of income, while males will exhibit an abnormal sexual drive for uncommon or taboo sexual acts, although the ability to get and retain an erection is lost. Loved ones of methheads must learn to dissociate from their victimized friends and keep them away, as property theft is a favorite methhead occupation. Use of expensive surveillance equipment is a must (if they even have a house) and crime to them becomes completely justifiable. The recovery rate among methamphetamine addicts is around 20%; the other 80% remain menaces to society. Almost all have criminal records. Other common synonyms: spinner (usually females), tweeker, thwacker, speed freak.
That methhead bitch gave me HepC, stole my gun and wasn't even a good piece of ass!