Captopril is rapidly absorbed after oral administration with bioavailability of 70%. It is highly protein bound. It is excreted via Kidneys.
HYPERTENSION: Mild to moderate: 25-50mg t.i.d. Moderate to severe 50-100mg t.i.d
CONGESTIVE FAILURE: Start with 6.25-12.5mg. Build up to maintenance dose of 25mg 2 or 3 times/day. Max daily dose 150mg. Children: 1-6mg/kg daily in divided dose. Eldery: Start with lower dose and build up gradually. Renal impairment: Start with low doses and build up slowly. Captorpril may be combined with diuretic and other antihypertensives
Captopril inhibits angiotension converting enzyme which has two-fold effect; reduction of angiotension II levels (ATII) and increase of bradykinin levels. Both contribute to fall in BP, the former to a greater extent. Reduction of ATII also reduces Aldosterone and sodium and water retention. By these mechanisms captopril produces a hypotensive effect and a beneficial effect in congestive heart failure.
Risk of bone marrow depression when used with immunosupressive agents. Causes hyperkalaemia with potassium sparing diuretics. NSAID’s may block the hypotensive action of Captopril.
Effect & Precaution
Dry coug, skin rash, loss of taste, hyprkalaemia, vertigo, headache, nausea, vomiting, hypotension, fatigue, neutropenia, (rare), proteinuria, anaemia
Allergies: Allergic reaction to captopril may occur.
Pregnancy: Studies in animals at doses up to 400 times the human dose
have shown that captopril causes an increase in deaths of the foetus and
new born. Also, captopril has caused deformed skulls in the offspring of
rabbits given doses 2 to 70 times the recommended human dose.
Breast-feeding : captopril passes into breast milk.Children : Children
may be especially sensitive to the hypotensive effect of ACE inhibitors.
This may increase the chance of adverse effects during treatment.
Adults: This drug has been tested in patients 65 years of age or older
and has not been shown to cause any different side effects or problems
in older people than it does in younger adults.
Breast Feeding: Use with caution.
Man: May be used with caution.