Enalapril is an ACE inhibitor used for high blood pressure, heart failure and to protect the kidneys in diabetes. Common strengths are 5 mg, 10 mg and 20 mg. A persistent dry cough is its best-known side effect, and it must be stopped in pregnancy.
What is Enalapril?
Enalapril is an angiotensin-converting enzyme inhibitor — an ACE inhibitor. It is sold under several brand names in South Africa and, like most established medicines here, widely as the generic name.
The body has a hormone system that raises blood pressure. Angiotensin-converting enzyme turns angiotensin I into angiotensin II, and angiotensin II is a powerful vessel-narrowing hormone that also prompts the body to retain salt and water. Enalapril blocks that enzyme. Less angiotensin II means arteries relax and less fluid is retained, so blood pressure falls.
That is the blood pressure effect, and it is only part of the reason ACE inhibitors are prescribed so widely. Angiotensin II also drives structural change in the heart and the kidneys over years. Blocking it does more than lower a number: in heart failure, ACE inhibitors reduce hospital admissions and prolong life, and in diabetic kidney disease they slow the loss of kidney function. Those are benefits a blood pressure reading does not show.
It is a Schedule 3 medicine.
What is Enalapril commonly used for?
Enalapril is prescribed for:
- High blood pressure, alone or combined with other medicines.
- Heart failure, where it is a cornerstone of treatment rather than a symptom reliever.
- After a heart attack, to protect the heart muscle from harmful remodelling.
- Diabetic kidney disease, to slow progression — often prescribed even when blood pressure is not particularly high.
- Chronic kidney disease with protein in the urine, for the same reason.
The kidney use catches people out. Being given a “blood pressure tablet” when your blood pressure is fine seems odd until the reason is clear: in diabetes, enalapril reduces the pressure inside the kidney’s filtering units and reduces protein leak, which slows the path toward kidney failure. It is prescribed for the kidneys, and the blood pressure effect comes along with it.
In heart failure, similarly, it is one of the medicines that changes the course of the illness — unlike a diuretic such as Defulide, which relieves fluid congestion very effectively but does not alter survival. Both have their place, and they are usually taken together.
How Enalapril fits into this medicine category
ACE inhibitors are one of the main groups used for blood pressure and heart failure:
| Group | Examples | How it works |
|---|---|---|
| ACE inhibitors | Enalapril, perindopril, ramipril | Blocks a vessel-narrowing hormone |
| ARBs | Losartan, valsartan | Same system, later step; no cough |
| Calcium channel blockers | Amlodipine (Ciplavasc) | Relaxes artery walls |
| Diuretics | Hydrochlorothiazide (Ridaq) | Removes excess salt and water |
| Beta blockers | Atenolol, carvedilol | Slows the heart, reduces its workload |
If the cough from an ACE inhibitor becomes intolerable, an ARB gives nearly the same benefits without it — a common and simple switch. See the heart, blood pressure and circulation medicines hub.
What to check before using Enalapril
Stop it and contact your doctor if you become pregnant or are planning to. ACE inhibitors cause serious harm to a developing baby, particularly after the first trimester. Anyone of childbearing age taking one should know this before it is needed. Safer alternatives exist for use in pregnancy.
Expect blood tests. Kidney function and potassium are checked before starting and after any increase. These are not routine paperwork — they detect the two effects that matter most.
Tell your prescriber or pharmacist if:
- You have kidney disease, or narrowing of the arteries to the kidneys.
- You have high potassium, or take a potassium supplement or a potassium-containing salt substitute.
- You take spironolactone or amiloride, which also raise potassium.
- You take an anti-inflammatory such as ibuprofen or diclofenac — the combination with a diuretic is particularly hard on the kidneys.
- You take lithium, or another blood pressure medicine.
- You have aortic stenosis or another significant valve narrowing.
- You have ever had angioedema — swelling of the face, lips, tongue or throat — from any cause.
- You are breastfeeding.
The first dose can drop blood pressure noticeably, particularly if you are on a diuretic. Take it when you can sit down afterwards.
Follow the dispensing label. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
The dry cough is real and common. A persistent, tickly, unproductive cough affects a meaningful proportion of people on ACE inhibitors — more so women — and it can begin weeks or months after starting. It is not an infection and cough mixtures do not help. It resolves within weeks of stopping. Do not simply endure it: an ARB provides the same protection without the cough, and switching is routine.
Angioedema is rare but an emergency. Swelling of the face, lips, tongue or throat, or sudden difficulty breathing or swallowing, requires immediate emergency care. It can occur after years of uneventful use, and anyone who experiences it must never take an ACE inhibitor again.
Potassium can rise, more so with kidney impairment or other potassium-raising medicines. Avoid salt substitutes, which are usually potassium chloride.
Kidney function may shift after starting or increasing. A small change is expected and monitored; a larger one prompts a review.
Dizziness is common early on and usually settles. Rise slowly.
Do not stop on your own, particularly in heart failure or kidney protection, where the benefit is not something you can feel.
Seek urgent medical attention for swelling of the face, lips, tongue or throat, difficulty breathing or swallowing, fainting, palpitations or marked muscle weakness, a significant reduction in urine, or yellowing of the skin or eyes.
Related medicine guides
- Browse Heart, Blood Pressure & Circulation Medicines guides
- Read: Ciplavasc used for
- Read: Ridaq used for
Frequently asked questions
What is enalapril 10 mg used for? High blood pressure, heart failure, protection after a heart attack, and slowing kidney damage in diabetes and chronic kidney disease.
Why am I on it when my blood pressure is normal? In diabetes and kidney disease it is prescribed to protect the kidneys by reducing protein leak and pressure inside the filtering units. The blood pressure effect is secondary there.
Why does it make me cough? Blocking ACE also affects substances that sensitise the airways. The cough is dry and persistent, is not an infection, and stops within weeks of switching to an ARB.
Can I take it in pregnancy? No. ACE inhibitors harm a developing baby. Contact your doctor if you become pregnant or are planning to, and do not simply continue.
Why do I need blood tests? To check kidney function and potassium, both of which enalapril can affect. Tests are done before starting and after any increase.
Can I use a salt substitute? Ask first. Most are potassium chloride, and enalapril already raises potassium.