The appetite is usually enhanced, while the sex drive may increase or decrease. Adverse reactions are relatively rare, and most can be attributed to adulterants frequently found in marijuana preparations. Marinol, a synthetic form of THC, is approved for use in reducing the nausea caused by chemotherapy. In the U.S. there were a number of successful efforts, especially in the 1970s, to reduce criminal penalties for possession and use of marijuana, but many of the resulting laws have since been modified or repealed. In moderation, caffeine is a mild stimulant that increases urination and the heart rate and rhythm.
Excessive intake can cause restlessness, insomnia, heart irregularities, and delirium.
Used therapeutically to treat chronic debilitating diseases, anabolic steroids have also been used by bodybuilders and athletes seeking increased muscle mass and enhanced strength and stamina. Such use is banned by the International Olympic Committee and other governing bodies in sports, and in 1988 a federal law made it illegal to distribute anabolic steroids for nontherapeutic uses. HGH is known to act on many aspects of cellular metabolism, but its most obvious effect is the stimulation of the growth of cartilage and bone in children. Excess HGH after puberty has little effect on skeletal growth but results in a disease known as acromegaly. HGH is also used illegally by bodybuilders and athletes to increase muscle mass.