Zestril

What is Zestril?

Blood pressure is the term used to describe the strength with which blood is pumped around your body. When a blood pressure reading is taken there are two numbers involved. The first number (the systolic pressure) shows the force with which your heart is pumping blood around your body. The second number (the diastolic pressure) shows the resistance in your blood vessels as the blood flows into them.

If your heart is pumping blood into narrow blood vessels, there will be more pressure in the vessels than if they were wide and the blood could move easily through them. This is known as high blood pressure, meaning that the blood faces a high level of pressure (or resistance) as it tries to move around the body.

If high blood pressure is left untreated it can lead to an increased risk of heart disease, stroke and heart attack.

High blood pressure is linked to lifestyle choices like smoking, drinking alcohol and being inactive. There are also some medical causes such as lupus, underactive thyroid and diabetes.

Zestril is a tablet that is taken once a day. It can help to lower blood pressure and reduce the risk of associated complications.

How does Zestril work?

Zestril contains an active ingredient called lisinopril,which belongs to a group of medicines called angiotensin-converting enzyme (ACE) inhibitors.

Angiotensins can cause blood vessels to become narrow and restricted, and this makes it difficult for blood to flow through them freely.

Lisinopril relaxes and widens blood vessels so that it’s easier for blood to be pumped into them. This widening decreases blood pressure and makes your heart’s job easier.

What doses of Zestril are there?

Zestril is available in three dosage sizes: 5mg, 10mg and 20mg. Your clinician will decide which dose is best for you. Most people start on a lower dose which is increased until the right dose is found.

How to take Zestril

Always take your medication exactly as prescribed by your clinician.

You will usually be told to:

• swallow the tablet whole with a drink of water.
• take the tablets at the same time each day.

When taking your first dose, you will usually be told to:

• take special care and lie down if you start to feel dizzy or light-headed.
• contact our clinician if you are concerned after taking Zestril for the first time.

Common dosages:

For high blood pressure

• Starting dose of 10mg once a day.
• Long term dose of 20mg once a day.

For heart failure

• Starting dose of 2.5mg once a day.
• Long term dose of 5mg - 35mg once a day.

After a heart attack

• Starting dose of 5mg within 24 hours of heart attack and 5mg one day later
• Long term dose of 10mg once a day.

For kidney problems caused by diabetes

• The recommended dose is either 10mg or 20mg once a day.

How long does it take Zestril to work?

The active ingredient in Zestril can start to reduce high blood pressure within a few hours, but the full effects of the medication can take a few weeks to become apparent.

If you’re taking Zestril for heart failure it can take from a few weeks to a few months for you to start feeling better.

After a heart attack, you may not feel that the tablets are making any difference because you’re not experiencing symptoms. Even if you feel no different when you start taking Zestril, it’s important to keep taking them after a heart attack because it’s likely that they are working as your clinician wants them to.

What should I do if I make a mistake when taking Zestril?

If you forget to take a dose of Zestril, take it as soon as you remember. If it’s almost time for you to take the next dose, skip the missed dose and carry on as normal.

Never take a double dose of Zestril.

If you take too much Zestril, seek medical attention immediately.

Medically reviewed by

Dr Daniel Atkinson

GP Clinical Lead

on August 02, 2022.

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