Can anxiety medication put you in a really good mood and two hours later make you very violent?

Iam not sure. I am concerned for my daughter, she is seeing a guy that has these moods and says it is anxiety pills. But this has happened a few times where he gets very violent and punches things and even banged the back of his head against a concrete wall and didn't remember doing it and had to have stitches. I am worried for her.

I would be too! This really doesn't sound like a side effect or it would happen consistently; it sounds like he needs professional help.
I hope it wouldn't happen again but next incidence like this should be reported to the police as an Emotional Disturbed Person. No more questionable excuses. My guess is he isn't going to take any advice from you or your daughter.
I don't suppose she would stop seeing this person???

That is what we try to tell her but she won't listen to her parents . Don't know what else to do.

There's only so much you can do. Hopefully she'll come to her senses before she gets hurt. Hope and pray.

Thank you I appreciate it your response. Sometimes my husband and I second guess ourselves but we know we are right.