I took 0.25 xanax, (alprazolam) is it ok if i drink 330ml beer after 4 hours?

Probably okay, but..: As a one time thing, it's probably okay. But if i were your physician i would be concerned about how often this is happening and whether this is part of a pattern that indicates risk of developing tolerance, physical dependence and/or addiction. Please make sure you discuss this with your doctor.

Xanax (alprazolam): Using xanax (alprazolam) together with alcohol can increase nervous system side effects such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. Avoid alcohol while being treated with xanax (alprazolam).