Allopurinol

Allopurinol is a prescription medication used to treat gout, high levels of uric acid, and kidney stones.  Allopurinol belongs to a group of drugs call xanthine oxidase inhibitors, which work by decreasing uric acid in the body. High levels of uric acid may lead to gout attacks or kidney stones.

This medication comes in tablet form and is taken once a day or in divided doses, with food and water. It is also in an injectable form to be given into the vein (IV) by healthcare professional.

Common side effects of allopurinol include diarrhea, nausea, and rash. Allopurinol can also cause drowsiness. Do not drive or operate heavy machinery until you know how allopurinol affects you.

Allopurinol is a prescription medication used to prevent gout, not to treat gout attacks once they occur.

It is also used to prevent kidney stones and high levels of uric acid in the body due to cancer treatment.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Allopurinol may be found in some form under the following brand names:

• Aloprim

• Lopurin

• Zyloprim

Allopurinol may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• diarrhea
• nausea (upset stomach)
• gout attacks

Some side effects can be serious. The following side effects occur less frequently, but if you experience any of them, call your doctor immediately:

• rash
• painful urination
• blood in the urine
• irritation of the eyes
• swelling of the lips or mouth
• fever, sore throat, chills, and other signs of infection
• loss of appetite
• unexpected weight loss
• itching

This is not a complete list of allopurinol drug interactions. Ask your doctor or pharmacist for more information.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• an ACE inhibitor
• cyclophosphamide (Cytoxan)
• mercaptopurine (Purinethol)
• azathioprine (Imuran)
• blood thinners such as warfarin (Coumadin, Jantoven)
• chlorpropamide (Diabinese)
• probenecid (Benemid)
• cyclosporine (Neoral, Sandimmune)
• didanosine (Videx, Videx EC)
• sulfinpyrazone (Anturane)
• a diuretic (thiazides)
• ampicillin (Omnipen, Principen, Polycillin)
• amoxicillin (Amoxil, Trimox)

This is not a complete list of allopurinol drug interactions. Ask your doctor or pharmacist for more information.

Serious allergic reactions including death have occurred with allopurinol. Stop taking this medication and talk to your doctor if you develop a skin rash.

Allopurinol, while it is used to prevent gout attacks, can temporarily cause flare-ups of gouty arthritis at the start of therapy. Your doctor may recommend another medication, such as colchicine, be taken along with allopurinol at first, to prevent these flare-ups.

Drink plenty of water or other fluids each day while taking allopurinol to prevent kidney stone formation.

Allopurinol can cause drowsiness. Do not drive a car or operate heavy machinery until you know how allopurinol affects you.

Serious liver problems have occurred with allopurinol use. While these events are rare, tell your doctor if you experience weight loss, lack of appetite, and itching. Your doctor will likely run tests to check your liver function.

Kidney failure has occurred in some people who took allopurinol.

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of allopurinol there are no specific foods that you must exclude from your diet when receiving allopurinol.

Before receiving allopurinol, tell your doctor about all of your medical conditions including if you:

• have liver or kidney disease
• are pregnant or breastfeeding
• are allergic to any medications, foods, dyes or preservatives

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Allopurinol falls into category C. There are no good studies that have been done in humans with allopurinol. In animals studies, pregnant animals were given this medication and had some babies born with problems. However, this medication may sometimes still help human mothers and their babies more than it might cause harm.

Tell your doctor if you are breastfeeding or plan to breastfeed. Allopurinol is found in breastmilk. Since the effect of allopurinol on the nursing infant is unknown, caution should be used when allopurinol is given to a nursing woman.

Tablets

• Allopurinol is a tablet to be taken by mouth, usually once a day or in divided doses.
• To avoid upset stomach, take allopurinol after a meal. Drink plenty of water or other fluids each day, unless directed to do otherwise by your doctor.
• If you miss a dose of allopurinol, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose. Do not take two doses at once.

Injection

• Allopurinol is available as an injectable form to be given into the vein (IV) by healthcare professional.
• If you miss a dose, be sure to make a follow up appointment.

Take allopurinol exactly as prescribed.

The dose your doctor recommends may be based on the following:

• the condition being treated
• other medications you are taking
• other conditions you have
• how your body responds to Aloprim
• your kidney function

Allopurinol Tablets

The adult dosage range is 100 mg to 800 mg. Your doctor will likely start you on a low dose and gradually increase the dose to avoid a flare-up of gout attacks which may occur when starting allopurinol. The recommended starting dose is 100 mg daily. The allopurinol dose is then increased by 100 mg each week based on the uric acid level in your blood.

• The maximum recommended dose is 800 mg. Doses higher than 300 mg should be divided into two or three smaller doses per day.

The adult dose for patients with cancer is allopurinol 600 mg or 800 mg daily (divided into two or three smaller doses per day) for two or three days, together with a high intake of fluids.

To prevent calcium oxalate kidney stones in adults is 200 mg or 300 mg per day, taken as a single dose or as a few (two or three) smaller doses throughout the day.

For children with cancer, ages 6 to 10, the recommended daily dose is 300 mg. Children under 6 years of age are usually given 150 mg allopurinol daily. 

Allopurinol Injection to lower high levels of uric acid in the body due to cancer treatment

• The recommended daily dose of Aloprim for adults is 200 to 400 mg/m²/day. The maximum daily dose is 600 mg.
• The recommended starting daily dose of Aloprim for children is 200 mg/m²/day.

If you take too much too much allopurinol, call your local Poison Control Center or seek emergency medical attention right away.

• Store allopurinol at room temperature away from excess moisture and light.
• Keep this and all medications out of the reach of children.