Comparative Pharmacology
Head-to-head clinical analysis: DYAZIDE versus METAHYDRIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DYAZIDE versus METAHYDRIN.
DYAZIDE vs METAHYDRIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Dyazide is a combination of hydrochlorothiazide, a thiazide diuretic that inhibits the Na+/Cl- cotransporter in the distal convoluted tubule, reducing sodium and water reabsorption; and triamterene, a potassium-sparing diuretic that blocks epithelial sodium channels in the collecting duct, reducing potassium excretion.
Metahydrin (trichlormethiazide) is a thiazide diuretic that inhibits the sodium-chloride symporter (NCC) in the distal convoluted tubule of the nephron, reducing sodium and chloride reabsorption and increasing excretion of water, sodium, chloride, and potassium.
1-2 capsules orally once daily; each capsule contains hydrochlorothiazide 25 mg and triamterene 50 mg.
Oral, 50-100 mg once daily. Maximum 200 mg/day.
None Documented
None Documented
Triamterene: 1.5–2.5 hours; hydrochlorothiazide: 6–15 hours. Clinical dosing typically once daily.
18-30 hours (clinically relevant for once-daily dosing in hypertension; prolonged in renal impairment)
Renal: triamterene ~80% (as metabolites and parent), hydrochlorothiazide >95% unchanged.
Renal: 30% (fecal: 70% as unabsorbed drug, primarily biliary elimination; <1% unchanged in urine)
Category C
Category C
Thiazide Diuretic
Thiazide Diuretic