Description
AXANTHINE OXIDASE INHIBITOR THAT DECREASES URIC ACID PRODUCTION. IT ALSO ACTS AS AN ANTIMETABOLITE ON SOME SIMPLER ORGANISMS.THIS COMPOUND BELONGS TO THE CLASS OF ORGANIC COMPOUNDS KNOWN AS PYRAZOLOPYRIMIDINES. THESE ARE COMPOUNDS CONTAINING A PYRAZOLOPYRIMIDINE SKELETON, WHICH CONSISTS OF A PYRAZOLE FUSED TO A PYRIMIDINE.
PHARMACOLOGY
PHARMACODYNAMICS:
Allopurinol, a structural analog of the natural purine base hypoxanthine, is used to prevent gout and renal calculi due to either uric acid or calcium oxalate and to treat uric acid nephropathy, hyperuricemia, and some solid tumors. Allopurinol and its active metabolite, oxypurinol, inhibits the enzyme xanthine oxidase, blocking the conversion of the oxypurines hypoxanthine and xanthine to uric acid. Elevated concentrations of oxypurine and oxypurine inhibition of xanthine oxidase through negative feedback results in a decrease in the concentrations of uric acid in the serum and urine.
PHARMACOKINETICS:
- Absorption: – Approximately 80-90% absorbed from the gastrointestinal tract.
- Protein binding: – Allopurinol and oxypurinol are not bound to plasma proteins.
- Metabolism: – Hepatic
- Elimination: -Approximately 20% of the ingested allopurinol is excreted in the feces.
- Half life: -1-3 hours
INDICATIONS:
For the treatment of hyperuricemia associated with primary or secondary gout.
Also indicated for the treatment of primary or secondary uric acid nephropathy, with or without the symptoms of gout, as well as chemotherapy-induced hyperuricemia and recurrent renal calculi.
