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Medications and Drugs

Brand Names: Zyloprim

Generic Name: allopurinol (Pronunciation: al oh PURE i nole)

What is allopurinol (Zyloprim)?

Allopurinol reduces the production of uric acid in your body. Uric acid buildup can lead to gout or kidney stones.

Allopurinol is used to treat gout or kidney stones, and to decrease levels of uric acid in people who are receiving cancer treatment.

Allopurinol may also be used for purposes not listed in this medication guide.

Allopurinol 100 mg-APO

round, white, imprinted with APO, ALL 100

Allopurinol 100 mg-MYL

round, white, imprinted with M 31

Allopurinol 100 mg-PAR

round, white, imprinted with 0524 0405

Allopurinol 100 mg-QUA

round, white, imprinted with 2083 V

Allopurinol 100 mg-SCH

round, white, imprinted with 5543, DAN DAN

Allopurinol 100 mg-URL

round, white, imprinted with MP 71

Allopurinol 100 mg-WAT

round, white, imprinted with 5543, DAN DAN

Allopurinol 300 mg-APO

round, orange, imprinted with APO, ALL 300

Allopurinol 300 mg-DAN

round, orange, imprinted with DAN DAN, 5544

Allopurinol 300 mg-MYL

round, white, imprinted with M 71

Allopurinol 300 mg-PAR

round, orange, imprinted with par 105

Allopurinol 300 mg-QUA

round, orange, imprinted with 2084 V

Allopurinol 300 mg-SCH

round, orange, imprinted with 5544, DAN DAN

Allopurinol 300 mg-URL

round, orange, imprinted with MP 80

Zyloprim 100 mg

round, white, imprinted with ZYLOPRIM 100

Zyloprim 300 mg

round, orange, imprinted with ZYLOPRIM 300

What are the possible side effects of allopurinol (Zyloprim)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using allopurinol and call your doctor at once if you have a serious side effect such as:

  • fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
  • the first sign of any skin rash, no matter how mild;
  • pain or bleeding when you urinate;
  • nausea, upper stomach pain, itching, loss of appetite, weight loss, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
  • urinating less than usual or not at all;
  • joint pain, flu symptoms;
  • severe tingling, numbness, pain, muscle weakness; or
  • easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin.

Less serious side effects may include:

  • vomiting, diarrhea;
  • drowsiness, headache;
  • changes in your sense of taste; or
  • muscle pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about allopurinol (Zyloprim)?

Do not use this medication if you have ever had a serious allergic reaction to allopurinol. Stop taking the medicine and call your doctor at once if you have any signs of skin rash, no matter how mild.

Take each dose with a full glass of water. To reduce your risk of kidney stones forming, drink 8 to 10 full glasses of fluid every day, unless your doctor tells you otherwise.

Allopurinol can lower blood cells that help your body fight infections. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood may need to be tested often. Visit your doctor regularly.

Avoid drinking alcohol. It can make your condition worse.

Allopurinol may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

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.

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