Ace%252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252525252520inhibitors

# ACE Inhibitors ## Overview Angiotensin-converting enzyme (ACE) inhibitors are a class of medications that block the action of ACE, an enzyme that plays a role in regulating blood pressure. By inhibiting ACE, these drugs prevent the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor. This leads to vasodilation, reduced aldosterone secretion, and ultimately, a decrease in blood pressure. ## Primary Indications * Hypertension * Heart Failure (HF) with reduced ejection fraction (HFrEF) * Myocardial Infarction (MI) - post-MI management for certain patients * Diabetic Nephropathy (in patients with diabetes and proteinuria) * Other Chronic Kidney Disease (CKD) with proteinuria ## Adult Dosing Dosing varies significantly by specific ACE inhibitor and indication. Typical starting doses and maximum doses for common agents are listed below: * **Benazepril:** Hypertension: Start 10 mg once daily, max 40 mg once daily. HF: Start 5 mg twice daily, max 10 mg twice daily. * **Captopril:** Hypertension: Start 25 mg twice daily, max 150 mg three times daily. HF: Start 6.25 mg three times daily, max 50 mg three times daily. * **Enalapril:** Hypertension: Start 5 mg once or twice daily, max 40 mg once daily. HF: Start 2.5 mg twice daily, max 10 mg twice daily. * **Lisinopril:** Hypertension: Start 10 mg once daily, max 40 mg once daily. HF: Start 5 mg once daily, max 20 mg once daily. * **Ramipril:** Hypertension: Start 2.5 mg once daily, max 10 mg once daily. HF: Start 2.5 mg twice daily, max 5 mg twice daily. Post-MI: Start 5 mg twice daily, max 10 mg twice daily. ## Pediatric Dosing * **Hypertension:** Dosing is established for some ACE inhibitors, but often requires careful titration and specialist guidance. * **Enalapril:** 6-12 years: Start 0.2 mg/kg/day in 2 divided doses, max 0.4 mg/kg/day. * **Lisinopril:** 6-12 years: Start 0.07 mg/kg once daily, max 0.21 mg/kg/day or 10 mg/day. * **Other indications:** Use in pediatric populations for HF, MI, and renal protection is generally off-label or requires expert consultation. ## Dose Adjustments * **Renal Impairment:** Dose reduction is often necessary, especially in patients with creatinine clearance less than 30 mL/min. Specific guidelines vary by drug and degree of renal impairment. * **Hepatic Impairment:** Generally not required, but caution is advised. ## Contraindications * History of angioedema related to previous ACE inhibitor treatment * Concomitant use with aliskiren in patients with diabetes mellitus or renal impairment * Pregnancy (Category D in 2nd and 3rd trimesters, Category X in 1st trimester) * Known hypersensitivity to the drug ## Adverse Effects * **Common:** Cough (dry, persistent), dizziness, fatigue, headache, hyperkalemia, hypotension. * **Serious:** Angioedema (can be life-threatening), acute kidney injury, severe hypotension, hepatotoxicity, neutropenia, rash. ## Key Drug Interactions * **Potassium-sparing diuretics/Potassium supplements/Salt substitutes:** Increased risk of hyperkalemia. * **NSAIDs/COX-2 inhibitors:** May reduce antihypertensive effect and increase risk of renal dysfunction, especially in the elderly or volume-depleted. * **Diuretics (especially thiazide or loop):** Increased risk of symptomatic hypotension. * **ARBs/Aliskiren:** Increased risk of hyperkalemia, hypotension, and renal impairment. Avoid concurrent use. * **Lithium:** ACE inhibitors can reduce lithium clearance, increasing the risk of lithium toxicity. * **mTOR inhibitors (e.g., sirolimus, everolimus), DPP-4 inhibitors (e.g., saxagliptin, linagliptin):** Increased risk of angioedema. ## Monitoring * **Baseline:** Blood pressure, serum creatinine, serum potassium, urinalysis (proteinuria). * **During therapy:** * Blood pressure (especially after initiation and dose changes). * Serum creatinine and potassium within 1-2 weeks of initiation/dose increase, and periodically thereafter. * Monitor for signs/symptoms of angioedema, cough, hypotension. ## Clinical Pearls * Cough is a common, often bothersome side effect, but angioedema is a more serious concern requiring immediate discontinuation. * Initiate at low doses and titrate slowly, especially in patients who are volume-depleted, have HF, or renal impairment. * Monitor renal function and potassium closely, particularly in patients with pre-existing renal disease or those taking concomitant diuretics or potassium supplements. * ACE inhibitors are generally considered safe and effective in patients with diabetes and can offer renal protection. * Discontinue immediately if angioedema occurs. A switch to an ARB is typically not recommended in patients with a history of ACE inhibitor-induced angioedema. *** *Disclaimer: This information is for educational purposes and does not substitute for professional medical advice. Always consult with a qualified healthcare provider to determine the best course of treatment for your specific condition and to ensure all current prescribing information is reviewed.*