Methamphetamine Methamphetamine is a powerful central nervous system stimulant. Even in small doses, the short-term effects of meth include wakefulness and decrease in appetite, which can cause users to loose severe amounts of weight. The short-term effects are fulfilling, however, the long-term effect are not as pleasant. Meth, after being used for some period of time, can cause a plethora of cardiovascular problems including irregular heartbeat. Meth creates a feeling of increased energy which, in some cases, can cause the body to be overworked to the point of physical and mental breakdown. Other effects include nausea, disturbed sleep patterns, increased aggressiveness, insomnia, hallucinations, anxiety, and paranoia. In some