Zyloprim is the brand name for allopurinol, a xanthine oxidase inhibitor. It is formulated as oral tablets containing either 100 mg or 300 mg of allopurinol. Inactive ingredients in the tablets include colloidal silicon dioxide, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate. The tablets are designed to be taken orally.

How should I use this medication?

Take this medication by mouth with a full glass of water. Take it as directed on the prescription label at the same time every day. You can take it with or without food. If it upsets your stomach, take it with food. Keep taking it unless your care team tells you to stop. Talk to your care team about the use of this medication in children. While this medication may be prescribed for children for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once. NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Where should I keep my medication?

Keep out of the reach of children and pets. Store at room temperature between 15 and 25 degrees C (59 and 77 degrees F). Protect from light and moisture. Throw away any unused medication after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible: -Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat -Kidney injury—decrease in the amount of urine, swelling of the ankles, hands, or feet -Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue -Rash, fever, and swollen lymph nodes -Redness, blistering, peeling, or loosening of the skin, including inside the mouth Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome): -Diarrhea -Drowsiness -Nausea -Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions: -Kidney disease -Liver disease -An unusual or allergic reaction to allopurinol, other medications, foods, dyes, or preservatives -Pregnant or trying to get pregnant -Breast-feeding

What may interact with this medication?

Do not take this medication with the following: -Didanosine, ddI This medication may also interact with the following: -Certain antibiotics like amoxicillin, ampicillin -Certain medications for cancer -Certain medications for immunosuppression like azathioprine, cyclosporine, mercaptopurine -Chlorpropamide -Probenecid -Sulfinpyrazone -Thiazide diuretics, like hydrochlorothiazide -Warfarin

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. If you are taking this medication to treat gout, you may not have less frequent attacks at first. Keep taking your medication regularly and the attacks should get better within 2 to 6 weeks. Drink plenty of water (10 to 12 full glasses a day) while you are taking this medication. This will help to reduce stomach upset and reduce the risk of getting gout or kidney stones. This medication may cause serious skin reactions. They can happen weeks to months after starting the medication. Contact your care team right away if you notice fevers or flu-like symptoms with a rash. The rash may be red or purple and then turn into blisters or peeling of the skin. You may also notice a red rash with swelling of the face, lips, or lymph nodes in your neck or under your arms. Do not take vitamin C without asking your care team. Too much vitamin C can increase the chance of getting kidney stones. This medication may affect your coordination, reaction time, or judgment. Do not drive or operate machinery until you know how this medication affects you. Sit up or stand slowly to reduce the risk of dizzy or fainting spells. Drinking alcohol with this medication can increase the risk of these side effects.