May 26, - The potent combination of Ativan and alcohol can cause instant blackouts and near death experiences, bringing your heart to a screeching halt. Alcohol can increase the nervous system side effects of LORazepam such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with LORazepam. Yesterday at around pm I was going to an event so I took mg of lorazepam and then stupidly ended up having a full night out drinking.