Allopurinol is an oral medication designed to block the production and release of uric acid in the blood. Buildups of uric acid can potentially cause several health problems, including kidney stones, bladder stones, and gout. Allopurinol helps prevent chronic conditions from worsening while other treatments are administered to combat existing symptoms. The drug is generally very effective, but it can cause unwanted side effects and leave the body more susceptible to infections. It is important for patients to discuss their health concerns and medication use before taking allopurinol to limit potential risks.
Uric acid is the product of metabolic processes that break down substances called purines. In normal amounts, the acid has important antioxidant properties. If levels rise too high, however, it can cause calcification of fluid and tissues. Uric acid buildup can calcify in the joints, leading to gout or causing painful stones in the urinary tract. Allopurinol is an inhibitor of an enzyme that promotes uric acid synthesis.
People who show signs of gout or kidney stones are commonly prescribed allopurinol in hopes of preventing further complications. It is also given to cancer patients who have recently undergone chemotherapy, as treatments tend to greatly increase uric acid levels in the body. Dosage amounts are determined on a patient-by-patient basis, but most adults with gout or stones are instructed to take 200 or 300 milligram tablets once or twice daily with water. In addition, it is important for patients to drink several glasses of water a day to help flush their kidneys and promote faster recovery. Dietary recommendations or restrictions may also be put in place when a person is prescribed allopurinol.
The most common side effects include diarrhea, nausea, and a mild skin rash. In addition, many people experience decreases in urine production, easy bruising, drowsiness, and joint pain. A small number of patients experience more severe side effects including high fever, muscle pains, tremors, seizures, and jaundice. It is important to seek immediate medical care if a serious allergic reaction causing hives and airway constriction occurs.
When patients attend regular checkups and take allopurinol according to their doctors' recommendations, they usually see relief from their symptoms within about a month. The drug does not actually heal acute episodes of gout or break apart existing kidney stones, but it can stop conditions from getting worse. If a patient experiences painful symptoms related to stones or gout, he or she may need to take additional medications or undergo surgical procedures to treat acute problems.