Comparative Pharmacology
Head-to-head clinical analysis: ALLOPURINOL versus FEBUXOSTAT.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ALLOPURINOL versus FEBUXOSTAT.
ALLOPURINOL vs FEBUXOSTAT
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Allopurinol inhibits xanthine oxidase, the enzyme responsible for the conversion of hypoxanthine to xanthine and xanthine to uric acid, thereby reducing serum and urinary uric acid concentrations. It also inhibits de novo purine synthesis through feedback inhibition.
Febuxostat is a non-purine selective inhibitor of xanthine oxidase (XO). It inhibits both oxidized and reduced forms of XO, thereby reducing the conversion of hypoxanthine to xanthine and xanthine to uric acid, leading to decreased serum uric acid levels.
100-600 mg orally once daily; initial 100 mg/day with weekly increases of 100 mg/day; maximum 800 mg/day.
40 mg orally once daily; may increase to 80 mg orally once daily if serum urate goal not achieved after 2 weeks.
None Documented
None Documented
Clinical Note
moderateAllopurinol + Hydrochlorothiazide
"The risk of a hypersensitivity reaction to Hydrochlorothiazide is increased when it is combined with Allopurinol."
Clinical Note
moderateAllopurinol + Bendroflumethiazide
"The risk of a hypersensitivity reaction to Bendroflumethiazide is increased when it is combined with Allopurinol."
Clinical Note
moderateAllopurinol + Methyclothiazide
"The risk of a hypersensitivity reaction to Methyclothiazide is increased when it is combined with Allopurinol."
Clinical Note
moderateAllopurinol: 1–2 hours; oxypurinol: 18–30 hours (prolonged in renal impairment).
Terminal elimination half-life: 5-8 hours in healthy subjects; prolonged in renal impairment (e.g., up to 9.6 hours in moderate impairment). Clinical context: dosing interval is once daily, consistent with half-life.
Renal: ~76% as unchanged drug and metabolites; oxypurinol (active metabolite) is primarily excreted renally. Biliary/fecal: minor, <5%.
Renal: 1-3% unchanged; biliary/fecal: ~50% as metabolites (acyl glucuronides, oxidative metabolites); other: ~49% metabolized and eliminated via multiple pathways including biliary and direct intestinal excretion of unchanged drug.
Category C
Category C
Xanthine Oxidase Inhibitor
Xanthine Oxidase Inhibitor
Allopurinol + Hydroflumethiazide
"The risk of a hypersensitivity reaction to Hydroflumethiazide is increased when it is combined with Allopurinol."