Zyloprim

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.

Dosage Forms & Strengths

tablet

• 100mg
• 300mg

powder for injection

• 500mg/vial

Gout

Mild: 100 mg/day PO initially; increased weekly to 200-300 mg/day

Moderate to severe: 100 mg/day PO initially; increased weekly to 400-600 mg/day

Antineoplastic-Induced Hyperuricemia

PO: 600-800 mg divided q8-12hr, starting 1-2 days before chemotherapy

IV: 200-400 mg/m²/day; not to exceed 600 mg/m²/day; may administer as single infusion or in equally divided doses at 6, 8, 12 hr intervals beginning 1-2 days before chemotherapy  

Dosing Considerations

Minimum PO dosage: 100-200 mg/day

Maximum PO dosage: 800 mg/day

Dosing Modifications

Renal impairment

• CrCl 10-20 mL/min: 200 mg/day
• CrCl 3-10 mL/min: 100 mg/day
• CrCl <3 mL/min: 100 mg/day at extended intervals

Dosage Forms & Strengths

tablet

• 100mg
• 300mg

powder for injection

• 500mg/vial

Hyperuricemia

10 mg/kg/day PO divided q12hr; not to exceed 600 mg/day  

Antineoplastic-Induced Hyperuricemia

PO (<6 years): 150 mg/day divided q8hr

PO (6-10 years): 300 mg/day in single daily dose or divided q8hr

PO (>10 years): 600-800 mg/day, starting 1-2 days before chemotherapy

IV: 200 mg/m²/day initially, starting 1-2 days before chemotherapy  

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Didanosine

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Azathioprine
• Captopril
• Cyclophosphamide
• Enalapril
• Enalaprilat
• Fluorouracil
• Mercaptopurine
• Pegloticase
• Tegafur

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Aluminum Hydroxide
• Cyclosporine
• Phenprocoumon
• Vidarabine
• Warfarin

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

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

Zyloprim, 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 Zyloprim at first, to prevent these flare-ups.

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

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

Serious liver problems have occurred with Zyloprim 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 Zyloprim.

Before receiving Zyloprim, 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.

• Zyloprim is a tablet to be taken by mouth, usually once a day or in divided doses.
• To avoid upset stomach, take Zyloprim 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 Zyloprim, 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.

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

Allopurinol is used to prevent or treat high uric acid levels in the blood. Gout or gouty arthritis (inflammation and pain in a joint) is caused by high uric acid levels. Allopurinol is a xanthine oxidase inhibitor that works by causing less uric acid to be produced by the body.

Allopurinol is also used to prevent or treat high uric acid levels that may be caused by cancer medicines or for patients with kidney stones that contain calcium.

This medicine is available only with your doctor's prescription.

• It is used to lower uric acid in the blood.
• It is used to prevent high uric acid levels during chemo.
• It may be given to you for other reasons. Talk with the doctor.

• Store at room temperature.
• Protect tablets from light.
• Store in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Check with your pharmacist about how to throw out unused drugs.

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else's drugs.
• Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
• Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine, please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take Zyloprim (allopurinol tablets) or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Zyloprim. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Review Date: October 4, 2017

THIS IS NOT AN INNOCUOUS DRUG. IT IS NOT RECOMMENDED FOR THE TREATMENT OF ASYMPTOMATIC HYPERURICEMIA.

Zyloprim reduces serum and urinary uric acid concentrations. Its use should be individualized for each patient and requires an understanding of its mode of action and pharmacokinetics (see CLINICAL PHARMACOLOGY, CONTRAINDICATIONS, WARNINGS, and PRECAUTIONS).

Zyloprim is indicated in:

1. the management of patients with signs and symptoms of primary or secondary gout (acute attacks, tophi, joint destruction, uric acid lithiasis, and/or nephropathy).
2. the management of patients with leukemia, lymphoma and malignancies who are receiving cancer therapy which causes elevations of serum and urinary uric acid levels. Treatment with Zyloprim should be discontinued when the potential for overproduction of uric acid is no longer present.
3. the management of patients with recurrent calcium oxalate calculi whose daily uric acid excretion exceeds 800 mg/day in male patients and 750 mg/day in female patients. Therapy in such patients should be carefully assessed initially and reassessed periodically to determine in each case that treatment is beneficial and that the benefits outweigh the risks.