Comparative Pharmacology
Head-to-head clinical analysis: HYDRALAZINE HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE versus INDERIDE LA 80 50.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDRALAZINE HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE versus INDERIDE LA 80 50.
HYDRALAZINE HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE vs INDERIDE LA 80/50
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydralazine is a direct-acting arteriolar vasodilator that reduces peripheral vascular resistance via relaxation of vascular smooth muscle, possibly by interfering with calcium transport. Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, increasing excretion of sodium and water, and reducing plasma volume.
Combination of propranolol (non-selective beta-blocker) and hydrochlorothiazide (thiazide diuretic). Propranolol blocks beta-1 and beta-2 adrenergic receptors, reducing heart rate, myocardial contractility, and blood pressure. Hydrochlorothiazide inhibits sodium-chloride symporter in distal convoluted tubule, increasing excretion of sodium, chloride, and water, reducing plasma volume.
Initially one capsule (25 mg hydralazine/25 mg hydrochlorothiazide, or 50 mg hydralazine/50 mg hydrochlorothiazide) twice daily, increase as needed to a maximum of 200 mg hydralazine/200 mg hydrochlorothiazide daily.
One capsule orally once daily, containing propranolol hydrochloride 80 mg (immediate release) and hydrochlorothiazide 50 mg. May be titrated based on response, with maximum propranolol dose 640 mg/day and maximum hydrochlorothiazide dose 50 mg/day.
None Documented
None Documented
Hydralazine: 2-8 hours (terminal, prolonged in renal impairment; acetylator phenotype affects clearance; slow acetylators have 2-fold longer half-life). Hydrochlorothiazide: 6-15 hours (terminal, prolonged in renal impairment; clinically relevant for once-daily dosing).
Propranolol: 3-6 hours (poor metabolizers up to 10 hours). Hydrochlorthiazide: 6-15 hours (prolonged in renal impairment).
Hydralazine: 90% renal (primarily as metabolites, 10-15% unchanged); Hydrochlorothiazide: >95% renal (unchanged). Biliary/fecal: negligible for both.
Renal elimination of propranolol and hydrochlorthiazide: propranolol is extensively metabolized in the liver, <1% excreted unchanged in urine; hydrochlorthiazide is excreted unchanged in urine (≥95% renal).
Category A/B
Category C
Thiazide Diuretic
Beta Blocker and Thiazide Diuretic