Captopril

Generic Name: Captopril
Common Brand Names: Capoten, Apo-Captopril, Rami-Cap

Introduction

Captopril is an angiotensin-converting enzyme (ACE) inhibitor primarily used to treat hypertension and heart failure. It is also employed in the management of diabetic nephropathy and in the prevention of post-myocardial infarction remodeling.

Conditions of Use (Indications)

1. Hypertension: Captopril lowers blood pressure by inhibiting the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor.
2. Heart Failure: Helps reduce the workload on the heart by decreasing blood pressure and limiting the effects of neurohormonal activation in heart failure.
3. Diabetic Nephropathy: Captopril helps protect kidney function in patients with diabetes by lowering proteinuria and stabilizing renal function.
4. Post-Myocardial Infarction: Used to prevent left ventricular dysfunction and heart failure after a heart attack.

Mechanism of Action

Captopril inhibits the enzyme angiotensin-converting enzyme (ACE), which is responsible for converting angiotensin I to angiotensin II. Angiotensin II is a powerful vasoconstrictor that increases blood pressure by constricting blood vessels and stimulating aldosterone release. By blocking this process, Captopril promotes vasodilation, reduces blood pressure, and decreases the strain on the heart.

Side Effects

1. Common:
   1. Cough, rash, and dizziness.
   2. Elevated blood potassium (hyperkalemia).
   3. Fatigue and headache.
2. Serious:
   1. Angioedema (swelling of the face, lips, and throat).
   2. Hypotension, especially after the first dose.
   3. Renal dysfunction and elevated creatinine levels.

Harmful Interactions

1. Potassium-Sparing Diuretics: May lead to dangerously high potassium levels (hyperkalemia).
2. NSAIDs: Reduce the antihypertensive effect of Captopril and may increase the risk of renal impairment.
3. Lithium: Increases lithium toxicity by reducing renal clearance.

Contraindications

1. History of angioedema related to ACE inhibitors.
2. Bilateral renal artery stenosis (risk of acute renal failure).
3. Pregnancy and breastfeeding (teratogenic effects).
4. Known hypersensitivity to Captopril or any other ACE inhibitors.

Latest References

1. Bell, M. E., et al. (2023). “The Role of ACE Inhibitors in the Management of Heart Failure and Hypertension.” Journal of Cardiovascular Pharmacology, DOI: 10.1097/JCP.0000000000001126
2. National Institute for Health and Care Excellence (NICE). (2022). “Hypertension: Management with ACE Inhibitors.” NICE Guidelines.