What is the fastest acting Angiotensin-Converting Enzyme (ACE) inhibitor?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 3, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the FDA Drug Label

In most patients studied, onset of antihypertensive activity was seen at one hour after oral administration of an individual dose of lisinopril, with peak reduction of blood pressure achieved by 6 hours

The most faster acting ACE inhibitor is Lisinopril, with an onset of action of 1 hour and peak reduction of blood pressure achieved by 6 hours 1.

  • Key points:
    • Onset of action: 1 hour
    • Peak reduction of blood pressure: 6 hours
  • Main idea: Lisinopril has a relatively fast onset of action compared to other ACE inhibitors.

From the Research

The fastest-acting ACE inhibitor is captopril, which begins working within 15-30 minutes after oral administration. Captopril is typically dosed at 12.5-25 mg orally, with effects peaking around 1-2 hours after intake. This rapid onset makes captopril particularly useful in hypertensive urgencies where quick blood pressure reduction is needed. The medication works by blocking the conversion of angiotensin I to angiotensin II, thereby reducing vasoconstriction and blood pressure. Unlike other ACE inhibitors that require hepatic activation, captopril is active in its administered form, explaining its faster onset. When using captopril, monitor for common side effects including hypotension, cough, hyperkalemia, and angioedema. The medication can be taken with or without food, though food may slightly delay absorption. For maintenance therapy, longer-acting ACE inhibitors like lisinopril or enalapril are often preferred due to their once-daily dosing convenience.

Some key points to consider when using captopril include:

  • Its rapid onset of action, making it suitable for hypertensive emergencies 2
  • The importance of monitoring for side effects, such as hypotension and hyperkalemia 3
  • The potential for captopril to be used in combination with other medications, such as diuretics and beta-blockers 4
  • The availability of alternative ACE inhibitors, such as lisinopril and enalapril, which may be preferred for maintenance therapy due to their longer duration of action 5, 6

Overall, captopril is a valuable option for the treatment of hypertension and heart failure, particularly in situations where rapid blood pressure reduction is necessary. Its efficacy and safety profile make it a commonly used medication in clinical practice 2.

Related Questions

Can a patient taking captopril (angiotensin-converting enzyme inhibitor) switch to enalapril (angiotensin-converting enzyme inhibitor) if captopril is unavailable, and are there any potential adverse effects?
Should Angiotensin-Converting Enzyme (ACE) inhibitors be taken with or without food?
What is the preferred initial treatment with Angiotensin-Converting Enzyme inhibitors (ACEi) or Angiotensin Receptor Blockers (ARB) for a patient with hypertension (High Blood Pressure) or heart failure, considering potential contraindications such as impaired renal function or hyperkalemia?
What are Angiotensin-Converting Enzymes (ACE)?
Does Angiotensin-Converting Enzyme Inhibitor (ACEI) improve quality of life in patients with Chronic Heart Failure?
What is cuboid syndrome?
What is the cause of a patient's left lower quadrant abdominal pain, constipation, dysuria, frequency, and hesitancy, despite a recent computed tomography (CT) scan of the abdomen and pelvis with intravenous (IV) contrast showing no acute disease, and a history of worsening symptoms since starting diabetes medication, specifically with symptoms of sharp pain, bloating, and difficulty having a bowel movement?
What is the optimal mean arterial pressure to maintain in neurogenic shock due to spinal cord (SC) injury?
What is the optimal mean arterial pressure to maintain in neurogenic shock due to spinal cord (SC) injury?
Is the use of corticosteroids (corticoides) indicated in spinal cord (raquimedular) trauma?
What are the differences between Multiple Endocrine Neoplasia (MEN) Type 1 and Type 2?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.