Drugs such as anabolic steroids, growth hormone and insulin used by some athletes have relatively minor side effects compared to more recreationally popular drugs such as alcohol and tobacco.
While the physical effects of anabolic drugs are well known, the psychological effects are shrouded in mystery and urban legend.
Researchers from the United Kingdom led by Peter Evans, in a review of literature, concluded that many of the psychological behaviors of anabolic drug users are pre-existing.
Female steroid users, for example, often take the drugs in response to previous sexual assault or to increase self-esteem. Psychological side effects are most common among anabolic steroid users and are more severe in athletes who take higher doses. A slight majority of steroid users (56 percent) become more psychologically active and irritable when taking the drug and about 40 percent are somewhat depressed when going off the drug.
However, growth hormone supplements improve cognitive ability in younger adults and improve mood, energy levels and quality of life in older adults. Most people use these drugs for cosmetic reasons rather than to improve athletic performance, so the psychological effects are more typically linked to pre-existing problems with self-esteem and vanity.