Recreational Drug Use and Human Aggressive Behavior: A Comprehensive Review Since 2003

Abstract 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 relationship 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 human aggressive behavior and alcohol. Recent studies also find cannabis use to be positively associated with human aggression, although personality factors may mediate this relationship during intoxication. While both cocaine and heroin have been strongly associated with aggressive behavior, this relationship is likely accounted for by third variable factors, such as personality traits and environmental influences. Methamphetamines have historically been associated with reduced aggression, although mounting research suggests increases in 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.