Comparative Pharmacology
Head-to-head clinical analysis: HYDRO RX versus METAHYDRIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDRO RX versus METAHYDRIN.
HYDRO-RX vs METAHYDRIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter (NCC) in the distal convoluted tubule of the nephron, reducing sodium and chloride reabsorption, leading to increased diuresis, decreased plasma volume, and vasodilation. It also reduces peripheral vascular resistance.
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.
Initial: 25 mg orally once daily; may increase to 50 mg once daily after 2 weeks based on response. Maximum: 50 mg daily.
Oral, 50-100 mg once daily. Maximum 200 mg/day.
None Documented
None Documented
Terminal elimination half-life is 8-12 hours in adults with normal renal function; extended to 20-30 hours in severe renal impairment (CrCl <30 mL/min).
18-30 hours (clinically relevant for once-daily dosing in hypertension; prolonged in renal impairment)
Renal excretion of unchanged drug accounts for 60% of elimination; biliary/fecal excretion accounts for 30%; 10% metabolized.
Renal: 30% (fecal: 70% as unabsorbed drug, primarily biliary elimination; <1% unchanged in urine)
Category C
Category C
Thiazide Diuretic
Thiazide Diuretic