Stories turn up all the time: altercations on airliners, brawls in bars, or domestic disputes that end in gunfire. The catchphrase is usually the same: “Alcohol was involved.” Alcohol often fuels less physically dangerous but more emotionally stressful confrontations at parties, business conclaves, or family dinner tables, manifested as cruel, hurtful words that can have devastating long-term effects on the recipients. The catchphrase? “That was the booze talking.” In Mean Drunk: Anger, Hostility, and Alcohol, William Tappan moves beyond the clichés and excuses to reveal the science behind the behavior. Drawing upon the latest scientific research in the field, illustrated by a broad array of dramatic case studies drawn from news stories, personal accounts, and his own decades of experience, Tappan defines and explains the hostility reaction to alcohol – HRA – as a specific neurobiological result of alcohol use. The evidence he presents points to cytokines: multifunctional proteins that trigger a defensive brain reaction to a perceived threat during alcohol consumption. Although firmly based in science, Mean Drunk also presents a series of shocking, moving, and sometimes bizarre stories of HRA as it leaves a trail of emotional damage, physical injury, and even death in its wake. From celebrities’ widely publicized encounters with the law (Reese Witherspoon, Mel Gibson) and headline-grabbing public fistfights precipitated by everyone from laborers to professionals to the most potentially damaging encounters – those within families – Mean Drunk lays out the horrific results catalyzed by the neurobiological cause. A groundbreaking explanation of HRA, Mean Drunk moves beyond accounts of human distress to point a way to greater understanding of an all-too-common and neglected problem for both perpetrators and victims, offering the possibility of their choosing a path to a happier and more productive life. Mean Drunk is a must-read for alcohol research professionals, counselors, those personally affected by HRA, and anyone interested in the causes of this devastating social and emotional puzzle.