- What is allopurinol, and how does it work (mechanism of action)?
- What brand names are available for allopurinol?
- Is allopurinol available as a generic drug?
- Do I need a prescription for allopurinol?
- What are the uses for allopurinol?
- What are the side effects of allopurinol?
- What is the dosage for allopurinol?
- Which drugs or supplements interact with allopurinol?
- Is allopurinol safe to take if I'm pregnant or breastfeeding?
- What else should I know about allopurinol?
What is allopurinol, and how does it work (mechanism of action)?
Allopurinol is used for treating gout caused by excessive levels of uric acid in the blood (hyperuricemia). It is a xanthine oxidase inhibitor and is similar to febuxostat (Uloric). Uric acid is a by product from the breakdown of certain proteins (purines) in the body by enzymes called xanthine oxidases. Hyperuricemia occurs when the body produces more uric acid than it can eliminate. The uric acid forms crystals in joints (gouty arthritis) and tissues, causing inflammation and pain. Elevated blood uric acid levels also can cause kidney disease and kidney stones. Allopurinol prevents the production of uric acid by blocking the activity of the enzymes that converts purines to uric acid. Uric acid levels usually begin to fall within 2-3 days of starting treatment and return to their original levels within 7-10 days after allopurinol is stopped. It may take several months of therapy before attacks of gout are controlled. The FDA approved allopurinol in August 1966.
What are the uses for allopurinol?
Allopurinol is used for preventing and/or treating acute attacks of gout, erosive destructive gouty joint disease, uric acid deposits in tissues (tophi), gouty kidney disease, and uric acid stones. Allopurinol also is used to prevent elevation of blood uric acid in patients undergoing chemotherapy for the treatment of certain cancers and in patients with recurrent calcium kidney stones and elevated uric acid levels.
What are the side effects of allopurinol?
Common side effects include:
Quick GuideGout Attack Symptoms, Causes, Treatment, and Diet
What is the dosage for allopurinol?
The dose of allopurinol for treating gout is 200-600 mg daily depending on severity. The dose for treating high uric acid blood levels due to chemotherapy is 100-800 mg daily starting 1 or 2 days before chemotherapy. It should be taken with food to avoid irritation of the stomach. In order to avoid formation of kidney stones, patients should drink plenty of fluids while taking allopurinol.
Which drugs or supplements interact with allopurinol?
: Allopurinol increases blood levels of oral mercaptopurine (Purinethol) and azathioprine (Imuran) by reducing their breakdown in the body. Therefore, the dose of mercaptopurine and azathioprine should be reduced in order to avoid toxicity. There is an increased risk of skin rash in patients taking allopurinol in combination with penicillins. Allopurinol may increase the effect of warfarin by reducing its breakdown.
Is allopurinol safe to take if I'm pregnant or breastfeeding?
There are no adequate studies of allopurinol in pregnant women.
What else should I know about allopurinol?
What preparations of allopurinol are available?
Tablets: 100, 300 mg; Powder for injection: 500 mg
How should I keep allopurinol stored?
Tablets should be stored at room temperature between 15 C to 25 C (59 F to 77 F) and in a moisture proof, light- resistant container. Powder should be stored from 20 C to 25 C (68 F to 77 F) and not refrigerated.
Multimedia: Slideshows, Images & Quizzes
Gout Attack Symptoms, Causes, Treatment, and Diet
Gout attacks (gouty arthritis) are caused by crystals of uric acid deposits. Learn about symptoms, causes, treatments and...
Gout Quiz: What is Gout? Is There a Gout Diet?
Learn what causes those painful crystals to form during a gout flare. Take the Gout Quiz to learn all about this painful...
Picture of Gout
Condition characterized by abnormally elevated levels of uric acid in the blood, recurring attacks of joint inflammation...
Picture of Fixed Drug Eruption
A large red-violet plaque on the arm of a child. See a picture of Fixed Drug Eruption and learn more about the health topic....
Related Disease Conditions
Treatment & Diagnosis
- Gout FAQs
- Prescriptions: Complying with the Doctor's Orders
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Drugs: Buying Prescription Drugs Online Safely
- Drugs: The Most Common Medication Errors
- Medication Disposal
- Dangers of Mixing Medications
- Generic Drugs, Are They as Good as Brand-Names?
Medications & Supplements
Prevention & Wellness
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Top allopurinol Related Articles
ChemotherapyChemotherapy is the treatment of cancer with drugs that can destroy cancer cells. These drugs often are called "anticancer" drugs. Chemotherapy is often used with other treatments. Coping with side effects (fatigue, nausea, vomiting, pain, hair loss, infection, diarrhea, constipation, fluid retention, mouth and throat problems) are important to understand when undergoing chemotherapy treatment. It is important to eat well during chemotherapy, and get the support you need both during and after treatment.
Chemotherapy Treatment for Breast CancerChemotherapy refers to medications that are administered to kill or slow the growth of cancerous cells. Chemotherapy may be given orally or intravenously. Side effects of breast cancer chemotherapy may include nausea, vomiting, hair loss, increased risk of infection, fatigue, and easy bruising. Receiving chemotherapy causes changes in a woman's menstrual cycle.
Drug InteractionsDrug interactions occur frequently. Get facts about the types of drug interactions, what substances or other things that may interact with drugs such as OTC drug and prescription drugs, vitamins, food(s) (grapefruit), and laboratory tests. Find out how to protect yourself from potential drug interactions.
Drugs: What You Should Know About Your DrugsImportant information about your drugs should be reviewed prior to taking any prescription drug. Side effects, drug interactions, warnings and precauctions, dosage, what the drug is used for, what to do if you miss a dose, how the drug is to be stored, and generic vs. brand names.
Fixed Drug Eruption PictureA large red-violet plaque on the arm of a child. See a picture of Fixed Drug Eruption and learn more about the health topic.
Gout (Gouty Arthritis)Buildup of uric acid crystals in a joint causes gouty arthritis. Symptoms and signs include joint pain, swelling, heat, and redness, typically of a single joint. Gout may be treated with diet and lifestyle changes, as well as medication.
Gout SlideshowGout attacks (gouty arthritis) are caused by crystals of uric acid deposits. Learn about symptoms, causes, treatments and medication for this painful condition.
Take the Gout QuizLearn what causes those painful crystals to form during a gout flare. Take the Gout Quiz to learn all about this painful arthritic condition.
Kidney StonesKidney stones are solid masses of crystalline material that form in the kidneys. Symptoms of kidney stones can include pain, nausea, vomiting, and even fever and chills. Kidney stones are diagnosed via CT scans and specialized X-rays. Treatment of kidney stones involves drinking lots of fluids and taking over-the-counter pain medications to medical intervention including prescription medications, lithotripsy, and sometimes even surgery.