What should I avoid while taking Allopurinol?

Allopurinol may cause drowsiness. You should avoid driving or operating machinery until you know how allopurinol affects you. You may need to avoid certain medications and foods while taking allopurinol. You should avoid purine-rich foods, such as anchovies, liver, kidneys and sardines. They can aggravate gout. You may need to avoid alcohol while taking allopurinol. Alcohol, especially beer and wine, can decrease the effectiveness of allopurinol. You should avoid vitamin C supplements. Excess consumption of vitamin C while taking allopurinol may increase your risk for certain kinds of kidney stones.