Recreational drug use and human aggressive behavior: A comprehensive review since 2003

Hundreds of studies have evaluated why drugs and aggression readily coexist and what static and transient physiological, environmental, and individual difference factors influence this relationship. While this literature is rapidly growing, there have been no comprehensive reviews on this relationship in the last decade. The present review summarizes the literature on the link between human aggressive behavior and alcohol, hallucinogens and psychedelics, methamphetamines, opioids, psychostimulants, anabolic-androgenic steroids, designer drugs, and depressants since 2003. Overall, studies show an unequivocal, causal, relationship between aggressive behavior and alcohol. Recent studies also find a positive relationship between cannabis use and aggressive behavior, although personality factors may mediate this relationship during intoxication. While research finds both cocaine and heroin to be strongly associated with aggressive behavior, this relationship is likely accounted for by third variable factors, such as personality traits and environmental influences. Studies also show increasing evidence that methamphetamines are associated with aggressive behavior during drug elimination and withdrawal. There is overwhelming experimental research suggesting that hallucinogens reduce aggressive behavior. Lastly, the relationship between morphine, codeine, designer drugs, and anabolic-androgenic steroids, ketamine, γ-Hydroxybutyric acid or GHB and human aggression remains sparse and inconclusive. Policy implications are briefly discussed.