Spironolactone 100mg

Spironolactone 100mg

Pharmacology
Mechanism of Action
Aldosterone antagonist with diuretic and antihypertensive effects; competitive binding of receptors at aldosterone-dependent Na-K exchange site in distal tubules results in increased excretion of Na+, Cl-, and water and retention of K+ and H+
Increases testosterone clearance and estradiol production; blocks conversion of potent androgens to weaker ones in peripheral tissues

Absorption
Increased with food
Bioavailability: 73% (tablet)
Onset: 2-4 hr (tablet)
Duration: 2-3 days (tablet)
Peak serum time: 3-4 hr (tablet); 0.5-1.5 hr (PO suspension); 2.5-5 hr (PO suspension, active metabolite)

Distribution
Protein bound: 90%

Metabolism
Metabolized by the liver and kidneys
Metabolites: Canrenone, 7-alpha-thiomethylspirolactone, 6-beta-hydroxy-7-alpha-thiomethylspirolactone (active)

Elimination
Half-life (tablet): Parent drug (1.3-1.4 hr); metabolite [canrenone] (9-23 hr)
Half-life (PO suspension): Parent drug (1-2 hr); metabolite [canrenone] (10-35 hr)
Excretion (tablet): Urine (47-57%); feces (35-41%)
Excretion (PO suspension): Urine

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Spironolactone 100mg only for the indication prescribed.