Allopurinol is used to treat gout and certain types of kidney stones. It is also used to prevent increased uric acid levels in patients receiving cancer chemotherapy. These patients can have increased uric acid levels due to release of uric acid from the dying cancer cells. Allopurinol works by reducing the amount of uric acid made by the body. Increased uric acid levels can cause gout and kidney problems.
Take this medication by mouth, usually once daily or as directed by your doctor. Take this medication after a meal to reduce stomach upset. If your dose is more than 300 milligrams a day, you will need to take several smaller doses during the day to get this amount (ask your doctor for directions).
It is best to drink a full glass of water with each dose and at least 8 more glasses (8 ounces each) of fluid a day. If your doctor has directed you to drink less fluid for other medical reasons, consult your doctor for further instructions. Your doctor may also instruct you on how to decrease acid in your urine (e.g., avoiding large amounts of ascorbic acid/vitamin C).
Dosage is based on your medical condition and response to treatment. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day.
For the treatment of gout, it may take up to several weeks for this medicine to have an effect. You may have more gout attacks for several months after starting this medicine while the body removes extra uric acid. Allopurinol is not a pain reliever. To relieve pain from gout, continue to take your prescribed medicines for gout attacks (e.g., colchicine, ibuprofen, indomethacin) as directed by your doctor.
Tell your doctor if your condition persists or worsens.