Effects of Nimodipine on Alcohol Drinking

This is a randomized placebo-controlled trial (RCT). Participants will be non-treatment seeking adults, 21-50 years of age, with Alcohol Use Disorders. All will participate in two alcohol drinking paradigm (ADP) sessions separated by at least 3 days at The Clinical Neuroscience Research Unit (CNRU). Participants will stay overnight and receive nimodipine (90 mg/dose) or placebo every six hours during an 18-hour period prior to each ADP. MEG and/or EEG data will be collected before the first dose and after the third dose of nimodipine (NIM) or placebo (PLA). Adverse events will be closely monitored during this period. During the ADP participants will receive a priming dose of alcohol followed by a one-hour monitoring period. This will be followed by three one-hour self-administration periods; during each hour they will be able to choose between four drinks or monetary equivalents of these drinks (total of 12 drinks over three hours). ADP outcomes will include number of drinks consumed, alcohol craving, mood changes and alcohol effects, physiological measures (heart rate, blood pressure), as well as breath alcohol levels. Investigators anticipate having to recruit up to 40 participants to achieve 20 completers.