Comparative Pharmacology
Head-to-head clinical analysis: ATENOLOL AND CHLORTHALIDONE versus METAHYDRIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ATENOLOL AND CHLORTHALIDONE versus METAHYDRIN.
ATENOLOL AND CHLORTHALIDONE vs METAHYDRIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Atenolol is a cardioselective beta-1 adrenergic receptor antagonist that reduces heart rate, myocardial contractility, and blood pressure. Chlorthalidone is a thiazide-like diuretic that inhibits sodium and chloride reabsorption in the distal convoluted tubule, reducing plasma volume and peripheral 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.
1 tablet (atenolol 50 mg/chlorthalidone 25 mg) orally once daily. May be increased to 2 tablets once daily.
Oral, 50-100 mg once daily. Maximum 200 mg/day.
None Documented
None Documented
Atenolol: 6-7 hours (prolonged to 14-27 hours in severe renal impairment); Chlorthalidone: 40-60 hours (allows once-daily dosing).
18-30 hours (clinically relevant for once-daily dosing in hypertension; prolonged in renal impairment)
Atenolol: ~50% eliminated unchanged in urine; Chlorthalidone: ~50-70% eliminated unchanged in urine, remainder as metabolites via renal and biliary routes (<10% fecal).
Renal: 30% (fecal: 70% as unabsorbed drug, primarily biliary elimination; <1% unchanged in urine)
Category C
Category C
Thiazide Diuretic
Thiazide Diuretic