Amphetamine is a central stimulant drug that affects the central nervous system. Smaller doses give feelings of increased energy, awareness and alertness. It can also reduce feelings of hunger and lead to higher blood pressure. The intoxication can last for several hours and larger doses may give the user an experience of fever, sweating, dizziness and headache. The increased stress on the body can lead to circulatory collapse, which is a directly life-threatening condition. When the positive emotions disappear, the drug leads to withdrawal symptoms of fatigue. Because amphetamines remove hunger pangs, long-term addiction can often lead to weight loss and diseases related to vitamin deficiency and malnutrition.