Enalapril

Uses

Enalapril has broad applications across cardiovascular and renal medicine, supported by decades of high-quality evidence:

• Hypertension: Effective in lowering both systolic and diastolic blood pressure across diverse populations. Especially useful in patients with diabetes, CKD, or established coronary artery disease. It reduces long-term risk of stroke, myocardial infarction, and kidney failure.
• Heart failure (HFrEF): Landmark trials (CONSENSUS, SOLVD) demonstrated enalapril reduces mortality and hospitalisations, improves symptoms, and delays progression. It remains a foundation of guideline-based therapy, often started at low dose and titrated upward alongside beta-blockers, MRAs, and SGLT2 inhibitors.
• Post–myocardial infarction: Starting enalapril within a few days of MI reduces adverse cardiac remodelling, recurrent events, and mortality.
• Diabetic nephropathy / CKD with proteinuria: Enalapril reduces proteinuria and preserves renal function, delaying need for dialysis or transplantation. This benefit extends even to patients with modest blood pressure elevations.
• Paediatric hypertension: In some regions, enalapril is approved for use in children ≥1 month of age with hypertension. Weight-based dosing is used, and careful monitoring of renal function and potassium is essential.

Dosing guidance

• Hypertension: start with 5–10 mg once daily; usual maintenance 10–40 mg daily in 1–2 divided doses.
• Heart failure: start low (2.5 mg twice daily), increase gradually to target 10–20 mg twice daily as tolerated.
• Post-MI: initiate within a few days if stable, often starting at 2.5 mg twice daily, titrating upward.
• Renal impairment: start lower, extend dosing intervals, and monitor renal function and electrolytes closely.

Patients are advised to continue lifestyle modifications (low-salt diet, exercise, weight management, smoking cessation) to complement pharmacological therapy. Enalapril is effective long-term only if taken consistently.

Side Effects

Enalapril, like all ACE inhibitors, has a predictable side effect profile. While most patients tolerate it well, some adverse reactions are common enough to warrant routine counselling.

Common

• Dry, persistent cough (up to 20% of users).
• Dizziness, headache, or lightheadedness.
• Fatigue, lethargy, or malaise.
• Gastrointestinal upset: nausea, diarrhoea, or abdominal pain.

Less common

• Skin rash, pruritus, or altered taste sensations.
• Elevated creatinine or mild increases in potassium.

Serious and rare — seek urgent care

• Angioedema: potentially life-threatening swelling of lips, tongue, face, or throat. Requires immediate discontinuation and emergency treatment.
• Severe hypotension: fainting, collapse, or shock, especially after the first dose in diuretic-pretreated or volume-depleted patients.
• Renal impairment: acute kidney injury in susceptible patients (renal artery stenosis, dehydration).
• Hyperkalaemia: dangerously high potassium leading to arrhythmias.

Most side effects resolve after discontinuation or dose adjustment. Alternatives such as ARBs may be used if ACE inhibitors are not tolerated.

Warnings & Precautions

• Pregnancy: Contraindicated. ACE inhibitors can cause severe foetal toxicity (renal failure, skull hypoplasia, oligohydramnios, foetal death). Stop immediately if pregnancy occurs.
• Breastfeeding: Enalapril is excreted in breast milk; not recommended.
• Renal impairment: Requires close monitoring and dose adjustment. Contraindicated in bilateral renal artery stenosis.
• First-dose hypotension: risk higher in dehydrated, salt-depleted, or diuretic-treated patients. Initiate under supervision if high risk.
• Hyperkalaemia: Monitor potassium levels, especially in patients with diabetes or CKD, or those taking potassium supplements/retaining agents.
• Older adults: May be more sensitive; start at lower doses.
• Surgery and anaesthesia: Withhold day of major surgery to reduce intra-operative hypotension.
• Other precautions: Bradykinin-related cough may necessitate therapy change; angioedema risk higher in black patients.

Patients should be counselled on monitoring blood pressure, recognising signs of angioedema, and reporting new or persistent cough.