Comparative Pharmacology
Head-to-head clinical analysis: DEMI REGROTON versus HYDRAP ES.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEMI REGROTON versus HYDRAP ES.
DEMI-REGROTON vs HYDRAP-ES
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
DEMI-REGROTON is a fixed-dose combination of chlorothiazide (a thiazide diuretic) and reserpine (a Rauwolfia alkaloid). Chlorothiazide inhibits the Na+-Cl- symporter in the distal convoluted tubule, reducing sodium and water reabsorption. Reserpine depletes catecholamines (norepinephrine, dopamine, serotonin) from central and peripheral nerve endings by inhibiting vesicular monoamine transporter 2 (VMAT2), leading to reduced sympathetic outflow and vasodilation.
Hydralazine is a direct-acting vasodilator that relaxes arteriolar smooth muscle, leading to decreased systemic vascular resistance and reduced blood pressure. The exact molecular mechanism involves inhibition of inositol trisphosphate (IP3)-induced calcium release from the sarcoplasmic reticulum and activation of guanylate cyclase, increasing cGMP levels.
One tablet orally once daily, each tablet containing 25 mg chlorthalidone and 0.125 mg reserpine.
Oral: 25-50 mg twice daily, max 200 mg/day. IV: 10-20 mg every 4-6 hours as needed.
None Documented
None Documented
Terminal elimination half-life is 40-60 hours (mean 48 h), allowing once-daily dosing; steady state reached in 5-7 days
Terminal elimination half-life is 2-4 hours in patients with normal renal function; prolonged in renal impairment (up to 20 hours in severe cases).
Renal: 70% as unchanged drug; biliary/fecal: 30% as metabolites
Primarily renal (80-90% as unchanged drug); minor biliary/fecal (<10%).
Category C
Category C
Antihypertensive Combination
Antihypertensive Combination