Please check your internet connection and try again.
## ACE Inhibitors
### Overview
Angiotensin-converting enzyme (ACE) inhibitors are a class of drugs primarily used to treat hypertension and heart failure. They work by blocking the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor, leading to vasodilation and reduced blood pressure.
### Primary Indications
* Hypertension
* Heart failure (systolic dysfunction)
* Myocardial infarction (post-MI patients with LV dysfunction or heart failure)
* Diabetic nephropathy (in patients with type 1 diabetes and hypertension)
* CKD (in patients with hypertension and proteinuria)
### Adult Dosing
Dosing is highly individualized and titrated based on patient response and tolerability. Usual starting doses and typical maintenance doses include:
* **Benazepril:** Start 5-10 mg once daily. Max 40 mg/day.
* **Captopril:** Start 12.5-25 mg twice daily. Max 150 mg three times daily.
* **Enalapril:** Start 2.5-5 mg once daily. Max 40 mg/day. (Oral: Max 40 mg/day. IV: Max 5 mg every 6 hours).
* **Fosinopril:** Start 10 mg once daily. Max 80 mg/day.
* **Lisinopril:** Start 5-10 mg once daily. Max 40 mg/day.
* **Moexipril:** Start 7.5 mg once daily. Max 30 mg/day.
* **Perindopril:** Start 2.5-5 mg once daily. Max 10 mg/day.
* **Quinapril:** Start 5-10 mg twice daily. Max 80 mg/day.
* **Ramipril:** Start 2.5 mg once daily. Max 10 mg/day.
* **Trandolapril:** Start 0.5-1 mg once daily. Max 4 mg/day.
### Pediatric Dosing
Dosing in children is less well-established and often requires specialized guidance.
* **Enalapril:** 0.07 mg/kg/dose every 12 hours. Max 0.61 mg/kg/day (or 40 mg/day).
* **Captopril:** 0.3 mg/kg/dose every 8 hours. Max 1 mg/kg/dose every 8 hours (or 50 mg every 8 hours).
### Dose Adjustments
* **Renal Impairment:** Reduce initial dose and titrate cautiously. Monitor potassium and creatinine.
* Enalapril: CrCl <30 mL/min, start 2.5 mg/day.
* Lisinopril: CrCl <30 mL/min, start 5 mg/day.
* Ramipril: CrCl <40 mL/min, start 1.25 mg/day.
* **Hepatic Impairment:** Use with caution. Captopril and enalapril are less likely to accumulate.
* **Volume Depletion:** Initiate at lower doses.
### Contraindications
* History of angioedema related to previous ACE inhibitor treatment.
* Hereditary or idiopathic angioedema.
* Concomitant use with aliskiren in patients with diabetes.
* Pregnancy (contraindicated in the second and third trimesters).
### Adverse Effects
* **Common:** Dry cough, dizziness, fatigue, headache, hyperkalemia, hypotension.
* **Serious:** Angioedema (including laryngeal edema, potentially fatal), acute kidney injury, hepatic failure, agranulocytosis, severe hypotension.
### Key Drug Interactions
* **Diuretics (especially potassium-sparing):** Increased risk of hyperkalemia and hypotension.
* **Potassium supplements and Salt substitutes:** Increased risk of hyperkalemia.
* **NSAIDs:** May reduce antihypertensive effect and increase risk of renal impairment, especially in volume-depleted patients.
* **Aliskiren:** Increased risk of hyperkalemia, hypotension, and renal impairment. Avoid concurrent use, especially in patients with diabetes.
* **ARBs:** Increased risk of hyperkalemia, hypotension, and renal impairment. Generally avoid dual RAAS blockade unless specific indication and close monitoring.
* **Lithium:** Increased lithium levels and toxicity.
* **mTOR inhibitors (e.g., sirolimus, everolimus):** Increased risk of angioedema.
### Monitoring
* Blood pressure (before and after initiation/dose changes).
* Serum potassium.
* Renal function (serum creatinine, BUN).
* Signs/symptoms of angioedema.
* Signs/symptoms of hypersensitivity.
### Clinical Pearls
* Dry cough is a common, dose-limiting side effect, occurring in up to 20% of patients. If cough is bothersome, consider switching to an ARB.
* First-dose hypotension is a risk, especially in volume-depleted patients or those on diuretics. Administer the first dose at bedtime or in a monitored setting.
* Angioedema can occur at any time during therapy and is a medical emergency.
* Monitor potassium closely, especially in patients with renal impairment, diabetes, or those taking potassium-sparing diuretics or supplements.
* Discontinue ACE inhibitors if pregnancy is detected.
***
*This information is intended for healthcare professionals and does not replace comprehensive drug monographs or current prescribing information. Always verify current dosing, indications, contraindications, and safety information with up-to-date resources.*
