I-Cillin Ampicillin Allopurinol
ModerateWhen allopurinol and ampicillin are taken together, skin rashes seem to happen more often than when people take ampicillin without allopurinol. The same is reported for amoxicillin taken with allopurinol.
These medicines are often taken together with some care. Your doctor may change a dose, space them apart or check on you more often. Make sure your doctor and pharmacist know you take both.