Ace%252525252525252525252525252525252525252525252525252525252520inhibitors

# ACE Inhibitors ## Overview Angiotensin-converting enzyme (ACE) inhibitors are a class of medications 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) * Post-myocardial infarction (MI) * Diabetic nephropathy (especially in patients with proteinuria) * Chronic kidney disease (CKD) with proteinuria ## Adult Dosing Dosing varies significantly by specific ACE inhibitor and indication. Doses are typically initiated low and titrated upwards based on patient response and tolerability. * **Hypertension:** * Benazepril: 10-40 mg once daily. Maximum 40 mg/day. * Captopril: 25 mg 2-3 times daily. Maximum 150 mg 3 times daily. * Enalapril: 5-40 mg once or twice daily. Maximum 40 mg/day. * Fosinopril: 10-40 mg once daily. Maximum 80 mg/day. * Lisinopril: 10-40 mg once daily. Maximum 80 mg/day. * Moexipril: 7.5-30 mg once daily. Maximum 30 mg/day. * Perindopril: 2.5-10 mg once daily. Maximum 10 mg/day. * Quinapril: 10-80 mg once or twice daily. Maximum 80 mg/day. * Ramipril: 2.5-20 mg once daily. Maximum 20 mg/day. * Trandolapril: 1-8 mg once daily. Maximum 8 mg/day. * **Heart Failure:** Doses often higher than for hypertension, titrating to target doses where evidence supports efficacy. Dosing initiation and titration should follow established guidelines (e.g., ACC/AHA) and local protocols. * **Post-MI:** Typically initiated within 24 hours in stable patients. Doses similar to hypertension, titrating to target doses. ## Pediatric Dosing ACE inhibitors are used in pediatric populations for hypertension and sometimes heart failure, but dosing is highly variable and often off-label or based on specific guidelines. * **Hypertension:** * Enalapril: 0.1 mg/kg once daily, increasing to 0.5 mg/kg/day divided twice daily if needed. Maximum 40 mg/day. * Lisinopril: 0.07-0.2 mg/kg once daily. Maximum 20 mg/day. * Captopril: 0.3-0.5 mg/kg 3 times daily. Maximum 3 mg/kg/day or 150 mg/day. * *Dosing for other ACE inhibitors in pediatrics is less established and requires careful consideration of age, weight, and renal function.* ## Dose Adjustments * **Renal Impairment:** Dose reduction is often necessary, especially in severe renal impairment. Specific recommendations vary by drug and creatinine clearance. Monitor potassium closely. * **Hepatic Impairment:** Captopril and enalapril are less affected by hepatic impairment. Fosipril is a prodrug that requires hepatic activation, so caution is advised. ## Contraindications * History of angioedema related to previous ACE inhibitor treatment. * Hereditary or idiopathic angioedema. * Concomitant use with aliskiren in patients with diabetes or moderate to severe renal impairment. * Pregnancy (especially second and third trimesters). ## Adverse Effects * **Dry cough:** Most common, often dose-related. * **Hypotension:** Especially with the first dose or in volume-depleted patients. * **Hyperkalemia:** Risk increased in renal impairment and with concomitant potassium-sparing diuretics or potassium supplements. * **Angioedema:** Rare but potentially life-threatening. More common in Black patients. * **Renal dysfunction:** Can worsen pre-existing renal impairment, particularly in bilateral renal artery stenosis. * **Dizziness, fatigue, headache.** * **Rash, dysgeusia.** ## Key Drug Interactions * **Potassium-sparing diuretics (e.g., spironolactone, amiloride) and potassium supplements:** Increased risk of hyperkalemia. * **NSAIDs:** May blunt the antihypertensive effect and increase risk of renal dysfunction. * **Diuretics (especially loop and thiazide):** Increased risk of hypotension and hyperkalemia. * **Aliskiren:** Contraindicated in patients with diabetes or moderate to severe renal impairment due to increased risk of adverse events (hyperkalemia, hypotension, renal dysfunction). * **ARBs:** Increased risk of hyperkalemia and angioedema. Concomitant use is generally not recommended. * **Lithium:** ACE inhibitors can decrease lithium clearance, increasing lithium toxicity risk. ## Monitoring * **Blood pressure:** Regularly, especially during initiation and dose titration. * **Serum creatinine and electrolytes (especially potassium):** Baseline and periodically thereafter, more frequently in patients with renal impairment, heart failure, or those on diuretics. * **Renal function:** In patients with bilateral renal artery stenosis. * **Signs of angioedema.** ## Clinical Pearls * Initiate at low doses and titrate slowly, especially in elderly patients, those with heart failure, or renal impairment. * Counsel patients about the risk of cough and angioedema, and to seek immediate medical attention for swelling of the face, lips, tongue, or throat. * Monitor renal function and potassium closely, particularly within the first few weeks of therapy or after dose increases. * ACE inhibitors are generally considered safe and effective in pregnancy *before* the second trimester, but their use is contraindicated from the second trimester onwards due to risks of fetal harm. --- ***Disclaimer:** This information is intended for clinical use and is not a substitute for professional medical advice. Always consult the most current prescribing information and relevant clinical guidelines for complete details before making any treatment decisions. Dosing and recommendations can vary based on individual patient factors, local protocols, and evolving medical knowledge.*