What is the MOA of allopurinol?

What is the MOA of allopurinol?

Mechanism of Action Allopurinol and oxypurinol both inhibit xanthine oxidase, an enzyme in the purine catabolism pathway that converts hypoxanthine to xanthine to uric acid.

What is the half life of allopurinol?

Allopurinol has a plasma half-life of about 1 to 2 hours. Oxipurinol is a less potent inhibitor of xanthine oxidase than allopurinol, but the plasma half-life of oxipurinol is far more prolonged. Estimates range from 13 to 30 hours in man.

Where is allopurinol absorbed?

If allopurinol is liberated in the duodenum or upper jejunum its absorption is fast and complete while its liberation in the lower jejunum results in a slow and incomplete absorption.

How is allopurinol distributed in the body?

Distribution: Distributed widely throughout the body except in the brain, where drug levels are 50% of those found in the rest of the body. Allopurinol and oxypurinol aren’t bound to plasma proteins. Metabolism: Metabolized to oxypurinol by xanthine oxidase.

Is allopurinol water soluble?

Allopurinol is a commonly used drug in the treatment of chronic gout or hyperuricaemia associated with treatment of diuretic conditions. One of the major problems with the drug is that it is practically insoluble in water, which results in poor bioavailability after oral administration.

What is the onset of action of allopurinol?

The onset occurs between 6 weeks to 6 years after allopurinol initiation. Varying degrees of bone marrow depression affecting one or more cell lines may occur (rare) in patients receiving allopurinol alone.

Does allopurinol weaken immune system?

Allopurinol alters the expression of cytokines and mediators of immune cells in the systemic 2 tissue by decreasing plasma urate. Allopurinol alters the expression of cytokines and mediators of immune cells in the systemic tissue by decreasing plasma urate.

How long does it take for allopurinol to work?

It can take 2-3 months to become fully effective. It does not have any effect during a gout attack, although you should continue to take it regularly every day even if this happens. During the first few weeks of taking allopurinol, your blood levels of uric acid may rise for a short while before they fall.

Does allopurinol make you pee?

Drowsiness: This drug can cause drowsiness. You shouldn’t drive, use machinery, or do other tasks that require alertness until you know how it affects you. Fluid intake: You should drink at least 3.4 liters (14 cups) of fluids each day. This will help you urinate at least 2 liters (2 quarts) per day.

Is allopurinol an immunosuppressant?

Allopurinol demonstrated to have an immunosuppressive action when given at the dose of 200 microgram daily to the mice receiving skin grafts.

Can I chew allopurinol?

You can take allopurinol with or without food. Taking this drug after a meal and with lots of water may reduce your chance of upset stomach. You can cut or crush the allopurinol tablet.

What’s the maximum dose of allopurinol I can take?

< 6 years: 150 mg/day PO; maximum dosage information is not available for IV dosing. Allopurinol is primarily metabolized by hepatic oxidation. The drug is known to rarely cause hepatotoxicity, especially if there is preexisting hepatic and/or renal disease.

What is the active metabolite of allopurinol?

Allopurinol and its active metabolite inhibit xanthine oxidase, the enzyme that converts hypoxanthine to xanthine and xanthine to uric acid. Inhibition of this enzyme is responsible for the effects of allopurinol.

Why is the elimination of allopurinol reduced in old age?

Although allopurinol elimination is not reduced in the aged, that of its active metabolite oxipurinol is because of an age-dependent decline in renal function. Xanthine oxidase inhibition by oxipurinol appears to be reduced in old age.

Why do I get a gout flare after taking allopurinol?

The rate of infusion depends on the volume of infusate. Gout flares may occur after initiation of urate lowering therapy, such as allopurinol, due to changing serum uric acid concentrations resulting in mobilization of urate from tissue deposits. If a gout flare occurs during treatment, allopurinol does not need to be discontinued.