🫀 Medication Guide

ACE inhibitor / Antihypertensive and heart-protective agent

Lisinopril

Blood pressure medication that also protects the heart, kidneys, and blood vessels.

Lisinopril is an ACE inhibitor — one of the most important classes of cardiovascular medications. It treats high blood pressure and protects the heart, kidneys, and blood vessels beyond simply lowering blood pressure. It is a cornerstone of treatment for heart failure, after heart attacks, and for people with diabetes and kidney disease.

What It Is Used For

✓ Hypertension (high blood pressure)

✓ Heart failure (to reduce strain on the heart)

✓ After heart attack (to protect heart muscle)

✓ Diabetic kidney disease (to slow progression)

✓ Chronic kidney disease (to reduce proteinuria)

How It Works

ACE inhibitors block the angiotensin-converting enzyme (ACE), which normally causes blood vessels to narrow and promotes sodium retention. By blocking ACE, lisinopril causes blood vessels to relax, reduces fluid volume, and lowers blood pressure. Crucially, it also reduces harmful pressure on the kidney filtration units (glomeruli) — protecting kidney function in people with diabetes or chronic kidney disease.

Dosing — Typical Guidance

Hypertension starting dose

5–10mg once daily. Increased gradually to 10–40mg once daily.

Heart failure

2.5mg once daily (very low starting dose) — increased gradually under close supervision

Diabetic kidney protection

10–20mg once daily — even in people without high blood pressure

Timing

Once daily. Can be taken at any time — consistency matters more than timing.

⚠️ Important Safety Note: Lisinopril and all ACE inhibitors are CONTRAINDICATED in pregnancy. They can cause severe fetal kidney damage and death. If you become pregnant while taking lisinopril, stop immediately and contact your doctor. Women of childbearing age should use effective contraception while taking lisinopril.

Side Effects

Very Common

Dry, persistent cough — the most common side effect, affecting 10–20% of people. Caused by bradykinin accumulation.

Not dangerous but bothersome. If intolerable, your doctor can switch to an ARB (e.g. losartan) which has the same benefits without the cough.

Common

Dizziness, especially when first standing — due to blood pressure lowering

Stand up slowly, particularly after the first few doses.

Serious (Rare)

Angioedema — sudden swelling of the lips, tongue, throat, or face. More common in Black patients (though still rare overall).

Medical emergency — stop lisinopril and seek emergency care immediately. Never restart.

Serious

High potassium (hyperkalaemia) — especially in people with kidney disease or taking potassium supplements

Potassium and kidney function monitored regularly.

Who Should Avoid This Medication

Who Should Not Take This (or Use With Caution)

⚠️ Pregnant women or women planning pregnancy — fetal harm is severe
⚠️ Previous angioedema with any ACE inhibitor — never rechallenge
⚠️ Bilateral renal artery stenosis (narrowing of both kidney arteries)
⚠️ Significant hyperkalaemia (high potassium before starting)

Drug Interactions to Know

Medication / Substance	Why It Matters
Potassium supplements or salt substitutes containing potassium	Lisinopril raises potassium. Combining can cause dangerously high potassium levels.
NSAIDs (ibuprofen, diclofenac)	Reduce the blood pressure-lowering effect of lisinopril and can worsen kidney function when combined. Avoid regular use.
ARBs (e.g. losartan)	Combining two RAAS blockers significantly increases risk of kidney damage and high potassium — avoid the combination.
Lithium	Lisinopril increases lithium levels. Close monitoring needed if both prescribed.

Monitoring While on This Medication

Blood pressure

At every medical visit — treatment target below 130/80mmHg in most adults

Kidney function (creatinine/eGFR)

Before starting, 1–2 weeks after starting, then annually. A small initial rise in creatinine (up to 30%) is expected and not a reason to stop.

Potassium (serum K+)

Before starting, then annually — or more often in kidney disease.

Frequently Asked Questions

Why does lisinopril make me cough?

Lisinopril prevents breakdown of bradykinin in the lungs, causing accumulation which triggers a dry cough. It is not dangerous but is bothersome. Switching to an ARB (angiotensin receptor blocker) eliminates the cough while providing the same cardiovascular benefits.

Is lisinopril safe for my kidneys?

For most people, yes — and it actively protects kidneys in people with diabetes or chronic kidney disease. A mild initial rise in creatinine is expected and acceptable. Significant or progressive decline requires assessment.

Can I take lisinopril if I have diabetes?

Yes — lisinopril is strongly recommended for people with diabetes who have any sign of kidney involvement (microalbuminuria or proteinuria), even if blood pressure is normal. It slows progression of diabetic kidney disease.

Does lisinopril protect the heart?

Yes. After a heart attack, lisinopril improves survival and prevents the heart from enlarging (remodelling). In heart failure, it reduces symptoms and hospitalisations significantly.

What should I do if my face starts swelling?

This is angioedema — a rare but potentially life-threatening reaction. Stop lisinopril immediately and go to the nearest emergency room. Do not restart. Tell all future doctors you have had angioedema with lisinopril — you must never take an ACE inhibitor again.