Comparative Pharmacology
Head-to-head clinical analysis: HYDRALAZINE HYDROCHLORIDE W HYDROCHLOROTHIAZIDE 50 50 versus INDERIDE 40 25.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDRALAZINE HYDROCHLORIDE W HYDROCHLOROTHIAZIDE 50 50 versus INDERIDE 40 25.
HYDRALAZINE HYDROCHLORIDE W/ HYDROCHLOROTHIAZIDE 50/50 vs INDERIDE-40/25
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydralazine is a direct-acting vasodilator that relaxes arteriolar smooth muscle via mechanisms involving interference with calcium ion movement and possibly nitric oxide release. Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, reducing sodium and water reabsorption and decreasing plasma volume.
Inderide-40/25 is a combination of propranolol (non-cardioselective beta-blocker) and hydrochlorothiazide (thiazide diuretic). Propranolol reduces heart rate, myocardial contractility, and renin secretion via beta-adrenergic receptor blockade. Hydrochlorothiazide inhibits Na+/Cl- cotransporter in distal convoluted tubule, increasing excretion of Na+, Cl-, and water; also reduces peripheral vascular resistance.
1 tablet (hydralazine 50 mg/hydrochlorothiazide 50 mg) orally twice daily, maximum 2 tablets daily.
One tablet (40 mg propranolol HCl/25 mg hydrochlorothiazide) orally twice daily; may increase to maximum of 160 mg propranolol/100 mg hydrochlorothiazide per day in divided doses.
None Documented
None Documented
Hydralazine: 2-8 hours (acetylator phenotype dependent; slow acetylators up to 8h, fast acetylators 1-2h). Hydrochlorothiazide: 6-15 hours (mean 10h).
Propranolol: 3-6 hours (terminal); clinical context: dosing 2-3 times daily due to short half-life; may accumulate in hepatic impairment. Hydrochlorothiazide: 6-15 hours (terminal); clinical context: longer in renal impairment.
Hydralazine: 80% renal (mainly as metabolites, 1-2% unchanged), 10% fecal. Hydrochlorothiazide: >95% renal (unchanged) via organic anion transporters.
Propranolol: extensively metabolized in liver via CYP2D6 and glucuronidation; <1% excreted unchanged in urine. Hydrochlorothiazide: ~70% excreted unchanged in urine via tubular secretion.
Category A/B
Category C
Thiazide Diuretic
Beta Blocker and Thiazide Diuretic