Acne and antibiotics

I’ve been taking antibiotics for a separate infection and noticed the pest acne bumps (tiny bumps, flesh colored) on my forehead and chin cleared up.

Is my acne caused by bacteria? I don’t wear face makeup (and on occasion that I do, I wipe it all off and wash face before bed), and wash my face and moisturize before bed.

If so, what should I do for acne caused by bacteria besides taking antibiotics (after I’m done with my course, that is). Anyone else experienced this? Thanks!