How long should I wait to drink after taking. 5 mg of ativan (lorazepam)? 24 hours?

Ativan (lorazepam) & alcohol. Ativan (lorazepam) will stay in your system for about 8 hours. The sedative effect of alcohol adds to the effect of the ativan (lorazepam). I would recommend avoiding alcohol for 6-8 hours after a dose and avoid driving.
Ativan (lorazepam) Ativan (lorazepam) usually lasts 4-6 hours, after that drinking in moderation is ok, assuming u r not intending to get drunk, as that causes need for more ativan (lorazepam).