It can be useful to distinguish between abuse and dependence. Alcohol abusers are those who persist in drinking despite occasional social, interpersonal, health, and legal issues arising from their alcohol use. Alcohol tolerance involves requiring increasing amounts over time to achieve the effects experienced previously. For instance, if you used to have three cocktails every night, you may now need five to attain the desired feeling. Withdrawal symptoms manifest as physical manifestations like insomnia, tremors, and mood swings after a short period without drinking.