From the Guidelines
Captopril is an angiotensin-converting enzyme (ACE) inhibitor medication primarily used to treat high blood pressure, heart failure, and diabetic kidney disease. It works by blocking the enzyme that converts angiotensin I to angiotensin II, a powerful vasoconstrictor, thereby relaxing blood vessels and reducing blood pressure. The typical starting dose is 6.25 mg 3 times daily, with a target dose of 50 mg 3 times daily, as recommended by the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. Captopril should be taken on an empty stomach, one hour before meals, as food can reduce its absorption. Common side effects include dry cough, dizziness, and taste disturbances. Patients should be aware that captopril can cause a significant drop in blood pressure with the first dose, so it's often recommended to take the initial dose at bedtime. It's essential to monitor kidney function and potassium levels while taking this medication, as ACE inhibitors can affect both, and the treatment should be individualized based on the patient's condition and response to therapy, as suggested by the ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 2012 1. Captopril is contraindicated during pregnancy as it can cause birth defects, and patients should immediately inform their doctor if they become pregnant while taking this medication. Some key points to consider when prescribing captopril include:
- Starting with a low dose and gradually increasing as needed and tolerated
- Monitoring renal function and electrolyte levels regularly
- Avoiding use in patients with symptomatic hypotension, azotemia, or hyperkalemia
- Considering alternative treatments, such as isosorbide dinitrate and hydralazine, in patients who cannot tolerate ACE inhibitors, as recommended by the guidelines for the evaluation and management of heart failure 1.
From the FDA Drug Label
Captopril is a specific competitive inhibitor of angiotensin I-converting enzyme (ACE), the enzyme responsible for the conversion of angiotensin I to angiotensin II. Captopril is designated chemically as 1-[(2S)-3-mercapto-2-methylpropionyl]-L-proline. The answer is: Captopril is an ACE inhibitor.
- Key points about captopril are:
- It is a competitive inhibitor of angiotensin I-converting enzyme (ACE)
- It is used in the form of oral tablets
- The chemical name is 1-[(2S)-3-mercapto-2-methylpropionyl]-L-proline 2
From the Research
Definition and Properties of Captopril
- Captopril is an orally active inhibitor of angiotensin-converting enzyme (ACE) 3, 4, 5, 6, 7.
- It has been used extensively in the treatment of patients with hypertension and congestive heart failure 3, 4, 5, 6, 7.
Therapeutic Efficacy
- Captopril is effective in the management of mild to moderate essential hypertension, severe hypertension, and congestive heart failure 3, 4, 5, 6, 7.
- It has been shown to improve cardiac performance, exercise tolerance, and functional classification, with associated reduction of clinical symptomatology 4, 7.
- Captopril has also been found to reduce mortality and morbidity in patients with acute myocardial infarction 5.
Side Effects
- Common side effects of captopril include skin rashes, proteinuria, and neutropenia 3, 4, 6, 7.
- Less common side effects include reduced renal function, dysgeusia, and symptomatic hypotension 3, 4, 6, 7.
- Captopril is generally well tolerated, but patients should be monitored for potential side effects 4, 5, 7.
Comparison to Other Treatments
- Captopril has been compared to other ACE inhibitors, such as enalapril, and has been found to have similar efficacy and tolerability 4.
- It has also been compared to other treatments, such as digoxin and prazosin, and has been found to have a similar or better response in certain patient populations 4, 5.