What Lisinopril Does
Lisinopril blocks ACE (angiotensin-converting enzyme), which normally causes blood vessels to constrict. By blocking ACE, blood vessels relax, blood pressure falls, and the heart and kidneys are protected from pressure damage.
| Condition | Typical Dose | Goal |
|---|---|---|
| Hypertension | 5–40 mg once daily | BP <130/80 mmHg |
| Heart failure | 2.5–35 mg once daily | Reduce symptoms, hospitalisation |
| Diabetic kidney disease | 10–20 mg once daily | Reduce protein leak (ACR) |
| Post heart attack | 5–10 mg once daily | Reduce mortality |
The ACE CoughAbout 1 in 5 people develop a persistent dry tickly cough on lisinopril. This is a class effect — not an allergy. If it's troublesome, you can switch to an ARB (e.g. losartan) which works the same way without the cough.
Blood Tests to Monitor
| Test | Timing | Why |
|---|---|---|
| Potassium | 1–2 weeks after starting / dose change | ACE inhibitors raise potassium |
| Creatinine / eGFR | 1–2 weeks after starting | A rise of <30% is acceptable |
| Blood pressure | 1–4 weeks after each change | Ensure BP at target |
| Urine ACR | Annually in diabetics | Monitor kidney protein leak |
First-Dose WarningThe first dose of lisinopril can cause a significant drop in blood pressure, especially if you are dehydrated or on diuretics. Take the first dose at night and get up slowly in the morning.
What to Avoid on Lisinopril
- NSAIDs (ibuprofen, naproxen) — raise blood pressure and potassium
- Potassium supplements or potassium-sparing diuretics — dangerous hyperkalaemia
- Salt substitutes — most contain high potassium
- Pregnancy — ACE inhibitors are teratogenic (harm the baby)
- Combined with another ACE inhibitor or ARB
Can I take ibuprofen with lisinopril?
Generally no. NSAIDs block the blood pressure lowering effect of lisinopril and can cause dangerous rises in potassium and kidney damage. Use paracetamol instead.
My creatinine rose after starting lisinopril — should I stop?
A rise of up to 30% in creatinine is expected and acceptable — it reflects reduced intraglomerular pressure, which is the protective mechanism. Stop only if it rises >30% or potassium >5.5 mmol/L.
Does lisinopril protect kidneys in diabetes?
Yes. It reduces the pressure within kidney filters (glomeruli) and decreases protein leakage in the urine. It's recommended for all diabetics with any signs of kidney involvement.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.