Zestril (Lisinopril)
Complete patient guide for uses, dosage, side effects, and safety information
Prescription RequiredQuick Facts
What Is Zestril Used For?
Zestril contains the active ingredient lisinopril and belongs to a group of medicines called ACE inhibitors. It works by helping to relax and widen your blood vessels.
Primary Uses
Zestril is used to lower high blood pressure (hypertension), treat heart failure, and help patients who have recently had a heart attack recover.
How It Works
As an ACE inhibitor, Zestril helps control your blood pressure and improves heart failure symptoms, but it does not cure these conditions. This is why you must take it every day as prescribed.
Good to know: Zestril helps control your condition but doesn’t cure it, so consistent daily use is important for best results.
How to Take Zestril
Take Zestril exactly as prescribed by your doctor. The dose depends on your condition and other medicines you may be taking. Take it at the same time each day for best results.
Dosage Instructions
For high blood pressure: Usually start with 5mg to 10mg once daily, with most patients taking 10mg to 20mg daily. For heart failure: Usually start with 2.5mg once daily, increasing to 5mg to 20mg daily as needed. For heart attack: May start within 24 hours with 5mg, followed by another 5mg after 24 hours, then 10mg after 48 hours, continuing with 10mg once daily. Swallow tablets with water, with or without food.
What If You Miss a Dose?
If it’s almost time for your next dose, skip the missed dose and take your next dose at the regular time. Never take a double dose to make up for a missed one.
Important: Never take a double dose to make up for a missed dose – this could be dangerous.
Available Tablet Strengths
Side Effects
Like all medications, this medicine can cause side effects. Most are mild and temporary, but some require medical attention.
Common Side Effects
These side effects occur relatively frequently and usually don’t require emergency care:
- Mild stomach upset, nausea, diarrhea, stomach pain
- Impotence
- Dry cough
- Running nose or sinus pain
- Changes in smell
- Light-headedness or dizziness
- Headache
- Fatigue
- Hair loss or thinning
- Changes in taste
- Sleepiness or difficulty sleeping, strange dreams
Seek immediate medical attention if you experience:
- Changes in heart beat (faster beating)
- Yellowing of skin and/or eyes (jaundice)
- Tingling or numbness in hands and feet
- Severe abdominal pain
- Itchy skin rash, psoriasis, other skin problems
- Signs of frequent infections (fever, chills, sore throat, mouth ulcers)
- Passing less urine than normal
- Bruising more easily than normal
- Signs of dehydration (nausea, vomiting, muscle cramps, headache, drowsiness, tiredness)
- Hallucinations (seeing, feeling, or hearing things that aren’t there)
- Chest pain, angina
- Swelling of face, lips, mouth, tongue, or throat with difficulty swallowing or breathing
- Wheeziness, difficulty breathing
- Collapse, numbness or weakness of arms or legs
- Hives or nettle rash
- Fainting
Important Warnings
There are several important situations where Zestril should not be used or requires special caution.
Who Should Not Take Zestril
Do not take Zestril if you are allergic to lisinopril or any ingredients, have had allergic reactions to ACE inhibitors before (especially swelling of face, lips, tongue, or throat), have a family history of unexplained swelling of face/lips/tongue/throat, are undergoing hemodialysis, or are taking aliskiren-containing blood pressure medicines if you have diabetes or kidney problems.
Medical Conditions to Discuss
Tell your doctor if you have kidney problems or are on dialysis, low blood pressure, liver problems, diabetes, heart conditions like aortic stenosis or hypertrophic cardiomyopathy, diarrhea or vomiting, follow a very low salt diet, are receiving allergy desensitization treatment, or are taking mTOR inhibitors or NEP inhibitors.
Pregnancy and Breastfeeding
Zestril is not recommended during pregnancy and should not be used while breastfeeding or planning to breastfeed. The medicine may harm your baby through the womb or breast milk. Tell your doctor immediately if you become pregnant while taking Zestril.
Allergic Reactions: If you or family members have had swelling reactions to ACE inhibitors before, you may be allergic to Zestril too.
Drug Interactions
Several medicines can interfere with Zestril or be affected by it. Always tell your doctor about all medicines you’re taking.
- Other blood pressure medicines (angiotensin II receptor blockers like candesartan, valsartan, telmisartan)
- Medicines containing aliskiren
- Diuretic tablets (water tablets)
- Lithium for mental disorders
- Potassium tablets and salt substitutes containing potassium
- Anti-inflammatory medicines like indomethacin, naproxen, ibuprofen
- Heparin for blood clots
- Co-trimoxazole (sulfamethoxazole and trimethoprim)
- Gold injections for rheumatoid arthritis
- Insulin and diabetes medicines
- Blood clot dissolving medicines like alteplase
- mTOR inhibitors and NEP inhibitors
Alcohol & Driving
Zestril can cause dizziness, especially after the first dose or when the dose is increased. Be cautious with alcohol and driving until you know how the medicine affects you.
Alcohol
Your doctor may advise you to limit your alcohol intake. Drinking alcohol may make dizziness or light-headedness worse.
Driving and Operating Machinery
Be careful before driving or using machines until you know how Zestril affects you. The medicine may cause dizziness, especially after the first dose or dose increases. Make sure you know how you react before doing anything that could be dangerous if you’re dizzy.
Storage
Store Zestril below 30°C in a cool, dry place away from moisture, heat, and sunlight. Keep tablets in the blister pack until it’s time to take them. Don’t store in the bathroom, near a sink, in the car, or on window sills. Keep away from young children. Take expired or unwanted medicine to any pharmacy for safe disposal.
Overdose Information
If you think you’ve taken too much Zestril, seek urgent medical attention immediately. Taking too many tablets will likely make you feel light-headed, dizzy, or you may faint. Call the Poisons Information Centre (13 11 26), contact your doctor, or go to the nearest hospital Emergency Department, even if you feel fine.
Frequently Asked Questions
Your doctor will check your blood pressure regularly to make sure Zestril is working. The medicine helps control your condition but you must take it every day as it doesn’t cure high blood pressure or heart failure.
Yes, it doesn’t matter if you take Zestril before or after food. Swallow the tablet with a glass of water or other liquid.
Continue taking Zestril for as long as your doctor tells you. Since it helps control but doesn’t cure your condition, you must take it every day. Always speak to your doctor before deciding to stop taking any of your medicines.
Your doctor may advise you to limit your alcohol intake. If you drink alcohol, dizziness or light-headedness may be worse, especially since Zestril can cause these effects.
If it’s almost time for your next dose, skip the missed dose and take your next dose when you’re meant to. Do not take a double dose to make up for the missed dose.
Make sure you drink enough water during exercise and hot weather, especially if you sweat a lot. If you don’t drink enough water while taking Zestril, you may faint or feel light-headed or sick because your blood pressure may drop suddenly.
Get up slowly when getting out of bed or standing up. You may feel light-headed or dizzy, especially if you’re also taking a diuretic. Standing up slowly helps your body get used to the change in position and blood pressure. Call your doctor if dizziness gets worse or continues.
Important Disclaimer
This information is intended for general educational purposes only and should not be considered medical advice. Always consult your healthcare provider or pharmacist before starting, stopping, or changing any medication.
If you think you may have a medical emergency, call your doctor or emergency services immediately.