Anabolic-androgenic steroids are found to have an effect on central nervous system functioning in people and laboratory animals. It is presumed that misuse of anabolic steroids can cause dependence and exposure to the use of toxicants and dependence on toxicants. Thus, people seeking treatment for steroid abuse increasingly use different kinds of toxicants concurrently .
This article focuses on a few of the most frequently used intoxicants: amphetamine, ecstasy, cocaine, cannabis and alcohol. Several of the research results on the mixed use of intoxicants are based on user interviews and animal testing with the primary steroid being nandrolone decanoate. However, many of these research results may also be universally applicable to the abuse of other anabolic steroids.
Steroid use lessens the pleasure caused by stimulants
Steroid use is often associated with amphetamine, MDMA (ecstasy), cocaine and other stimulating drugs. Their popularity may be explained by the effects described by steroid users, such as more effective training and activation of fat burning.
However, anabolic steroids are found to alter the rewarding effects of drugs. Taking nandrolone lessens the pleasure caused by amphetamine and ecstasy . Similar effects have also been found when interviewing users .
Because of the decrease in pleasure, steroid users may use larger drug doses to achieve the same pleasure level as users who don’t use steroids. As a consequence, the adverse effects of stimulants are significantly increased. For example, the risk of overdosing increases.
Using stimulants increases aggressive behavior related to the use of steroids, both in people  and laboratory animals. Amphetamine causes aggressive behavior even three weeks after the last nandrolone dose intake. Thus, using steroids may have a long term effect on an individual's behavior .
Both anabolic steroid and cocaine use change the functioning of heart. Concurrent use of these is found to increase the thickness of the left ventricle wall of the heart more than using either substance alone . Nandrolone further increases the accelerated heartbeat caused by cocaine use. Thus, the concurrent use of nandrolone and cocaine burdens heart significantly .
Steroids change the central nervous system sensitivity to cannabis
Some steroid users may use cannabis to improve their sleep and decrease stress. There are less studies about the concurrent use of cannabis and anabolic steroids than about the concurrent use of steroids and stimulating drugs.
Anabolic steroids also lessen the pleasure of cannabis use. Nandrolone lessens the rewarding effect of the active substance of cannabis, THC, in laboratory animals, but it simultaneously increases the withdrawal symptoms that appear after the use . Therefore, steroids possibly change the central nervous system sensitivity to cannabis.
Using alcohol and steroids concurrently adds aggressiveness
In laboratory animals, nandrolone increases the alcohol use for a long time after quitting the use of steroids. Together with abundant alcohol use, anabolic steroids further increase behavior problems caused by alcohol, such as losing control of things and self-control .
This may be a consequence of the effects of anabolic steroids on the functioning of the brain serotonin tractus . For example, concurrent use of nandrolone and alcohol lessens fear and timidity and significantly adds aggressive behavior compared to use of only alcohol . Thus, the use of anabolic steroids is sometimes connected to hate crimes, such as violent crimes .
These and several other research results support the assumption that anabolic steroids effect on an individual’s behavior and alter the effects of other toxicants by changing the biochemical functions of the central nervous system.
Ph.D., Senior Researcher
National Institute for Health and Welfare
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