Lisinopril
Is It Right for You?
A complete guide to Lisinopril — what it treats, how it works, dosages, side effects, and when a clinician may prescribe it following an online consultation.
What Is Lisinopril?
Lisinopril is an orally administered angiotensin-converting enzyme (ACE) inhibitor used for the treatment of hypertension, heart failure, myocardial infarction, and diabetic nephropathy. It is one of the most widely prescribed medications in the UK and globally, forming a cornerstone of cardiovascular and renal medicine. Unlike most ACE inhibitors (which are prodrugs requiring hepatic conversion to an active form), lisinopril is itself pharmacologically active — it does not require hepatic bioactivation, which is clinically relevant in patients with hepatic impairment.
Lisinopril is available generically and is supplied as 2.5 mg, 5 mg, 10 mg, and 20 mg tablets. It has a long half-life (approximately 12 hours) that supports once-daily dosing.
What Conditions Does Lisinopril Treat?
Lisinopril is prescribed for:
ACE inhibitors are foundational therapy for HFrEF. Lisinopril reduces cardiac preload and afterload, attenuates pathological ventricular remodelling, and reduces mortality and hospitalisation in patients with HFrEF. Multiple landmark trials (CONSENSUS, SOLVD) established the mortality benefit of ACE inhibitors in heart failure, and this class of drug is recommended in all patients with HFrEF in the absence of contraindications.
Early initiation of lisinopril after acute myocardial infarction (heart attack), particularly in patients with left ventricular dysfunction, reduces subsequent mortality and the development of heart failure. The GISSI-3 trial demonstrated reduced 6-week mortality with early lisinopril after MI. It is typically started within the first 24 hours in haemodynamically stable patients following acute MI.
Lisinopril is renoprotective in patients with diabetes and proteinuria, reducing intraglomerular pressure and slowing CKD progression — an effect that is over and above its blood pressure-lowering effect. It is recommended by NICE for all patients with type 1 or type 2 diabetes and microalbuminuria or proteinuria, with or without hypertension.
While Lisinopril is effective for managing hypertension and heart failure, it should be used cautiously in patients with a history of hypersensitivity or renal impairment.
How Does Lisinopril Work?
Angiotensin-converting enzyme (ACE) catalyses the conversion of the inactive decapeptide angiotensin I to the potent vasoconstrictor angiotensin II. ACE also inactivates bradykinin — a vasodilatory and natriuretic peptide. Lisinopril competitively inhibits ACE, producing two complementary effects: markedly reduced angiotensin II production (reducing vasoconstriction, aldosterone secretion, and sympathetic stimulation) and accumulation of bradykinin (contributing to vasodilation and, in the kidney, natriuresis and reduced intraglomerular pressure).
Reduced angiotensin II leads to: systemic vasodilation (lower blood pressure), reduced aldosterone secretion (less sodium and water retention, less potassium loss), attenuation of angiotensin II-mediated cardiac hypertrophy and ventricular remodelling, and reduced intraglomerular pressure (renoprotection). Bradykinin accumulation contributes to the blood pressure-lowering effect but is also responsible for the most common side effect: ACE inhibitor cough (see Side Effects).
Dosages & Administration
The correct dose depends on the type and severity of infection, age, weight, and kidney function. Always follow your clinician's instructions. The table below is for general reference only.
Administration Tips
Lisinopril tablets can be taken at any time of day, with or without food. Once-daily dosing at the same time each day is recommended for adherence. Tablets should be swallowed whole with water. Lisinopril does not require hepatic activation, making it suitable for patients with hepatic impairment who may poorly convert prodrug ACE inhibitors.
Side Effects of Lisinopril
Lisinopril is generally well tolerated, but some side effects may occur.
- Dizziness and hypotension: Particularly as first-dose hypotension; more pronounced in volume-depleted patients, those on diuretics, or those with heart failure. First dose at night is sometimes recommended to reduce symptomatic hypotension.
- Hyperkalaemia: Due to reduced aldosterone-mediated potassium excretion.
- Elevated creatinine: Expected modest rise (up to 30%) on initiation reflecting reduced intraglomerular pressure; acceptable and expected.
- Headache, fatigue
- Angioedema: Potentially life-threatening swelling of the face, lips, tongue, or throat. Occurs in approximately 0.1–0.2% of ACE inhibitor users and can occur at any time during treatment — not just at initiation. It is more common in Black patients and in those with a prior history of angioedema. Patients must seek immediate emergency care. Angioedema is a contraindication to all ACE inhibitors.
- Acute kidney injury: In bilateral renal artery stenosis or volume depletion; RAAS-dependent kidneys may decompensate on ACE inhibition.
- Neutropenia / agranulocytosis: Rare; more common in patients with collagen vascular disease (e.g. SLE, scleroderma) or renal impairment.
- Cholestatic jaundice and fulminant hepatic necrosis: Very rare but reported.
Patients should be informed about the risk of angioedema and the importance of seeking emergency care if they experience swelling.
Drug Interactions
Inform your clinician about all medications you are taking, as some drugs may interact with Lisinopril and affect its efficacy.
Additive effects may cause significant hyperkalemia (high potassium levels), which can lead to cardiac arrhythmias. Avoid routine combination unless closely monitored.
Concurrent use increases risk of hypotension, kidney impairment, and hyperkalemia. Dual blockade should generally be avoided unless specifically indicated.
Additive gastrointestinal irritation and antiplatelet effects increase the risk of gastrointestinal bleeding. Use cautiously and consider gastroprotection.
May enhance hypotensive effect, especially when starting lisinopril, increasing risk of dizziness or fainting. Monitor blood pressure during initiation.
Important Warnings
Swelling of the face, lips, tongue, or throat is a medical emergency. Call 999 immediately. Do not restart lisinopril or any other ACE inhibitor after an episode of angioedema.
Lisinopril must not be taken during pregnancy. It causes serious foetal harm and death. Use effective contraception; switch antihypertensives immediately if pregnant.
A persistent dry cough is a recognised and common side effect of lisinopril and all ACE inhibitors. It is not dangerous but is often distressing enough to require a switch to an ARB. Do not ignore a new persistent cough — it should be discussed with your clinician, as it may indicate ACE inhibitor intolerance rather than a respiratory illness.
Regular ibuprofen, naproxen, or diclofenac use significantly increases the risk of kidney injury and loss of blood pressure control while on lisinopril. Use paracetamol for pain relief.
Speak to a Clinician About Treatment
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The treatment you need, when you need it.
Lisinopril FAQs
Both lisinopril (ACE inhibitor) and losartan (ARB) block the renin-angiotensin system and have broadly equivalent blood pressure-lowering and organ-protective effects for most indications. The key practical difference is that ACE inhibitors cause a dry, persistent cough in 10–15% of patients (due to bradykinin accumulation), while ARBs do not. Patients who develop cough on lisinopril are typically switched to losartan or another ARB. Both classes are absolutely contraindicated in pregnancy.
Lisinopril affects both kidney function and potassium levels. Renal function and electrolytes should be checked before starting treatment, 1–2 weeks after initiation or dose change, and at least annually once stable (or more frequently if unwell, dehydrated, or if other medications change). A modest creatinine rise is expected and acceptable; a large or sharp rise, or significant hyperkalaemia, requires urgent review.
No. ACE inhibitor-induced cough is a class effect. Switching between different ACE inhibitors (e.g. from lisinopril to ramipril or perindopril) will not resolve the cough. The correct management is to switch to an ARB (such as losartan or candesartan), which achieves RAAS blockade without bradykinin accumulation and therefore does not cause cough.
Yes. Lisinopril and other ACE inhibitors are renoprotective in patients with diabetes and kidney disease. By reducing intraglomerular pressure and proteinuria, they slow the rate of progression of diabetic nephropathy beyond their blood pressure-lowering effect. They are recommended for all patients with diabetes and microalbuminuria or proteinuria, even if blood pressure is within the normal range.