Pyrimidine derivative. No data pointing to clinically significant CYP-induction. One reference consider it safe and one unsafe.

Tablets; 100-600 mg/d. Pyrazolopyrimidine. Used in gout where it blocks the enzyme xantine oxidase, thus decreasing plasma levels of uric acid. Rapidly metabolized to oxypyrinol (alloxantine) and other metabolites. South African list: use. French list: interdit. C.Andersson; patient reports: tolerated (n=3).

Uneventful use reported in 21 patients with acute porphyria.