MSI_000060367

Polythiazide is only found in individuals that have used or taken this drug. It is a thiazide diuretic with actions and uses similar to those of hydrochlorothiazide. (From Martindale, The Extra Pharmacopoeia, 30th ed, p826)As a diuretic, polythiazide inhibits active chloride reabsorption at the early distal tubule via the thiazide-sensitive Na-Cl cotransporter (TSC), resulting in an increase in the excretion of sodium, chloride, and water. Thiazides like polythiazide also inhibit sodium ion transport across the renal tubular epithelium through binding to the thiazide sensitive sodium-chloride transporter. This results in an increase in potassium excretion via the sodium-potassium exchange mechanism. The antihypertensive mechanism of polythiazide may be mediated through its action on carbonic anhydrases in the smooth muscle or through its action on the large-conductance calcium-activated potassium (KCa) channel, also found in the smooth muscle. D045283 - Natriuretic Agents > D004232 - Diuretics > D049993 - Sodium Chloride Symporter Inhibitors C78275 - Agent Affecting Blood or Body Fluid > C448 - Diuretic > C49185 - Thiazide Diuretic D002317 - Cardiovascular Agents > D000959 - Antihypertensive Agents D002317 - Cardiovascular Agents > D045283 - Natriuretic Agents D049990 - Membrane Transport Modulators