Why is Zestril prescribed?
Zestril is used in the treatment of high blood pressure. It is effective when used alone or when combined with other high blood pressure medications. It may also be used with other medications in the treatment of heart failure, and may be given within 24 hours of a heart attack to improve chances of survival.
Zestril is a type of drug called an ACE inhibitor. It works by reducing production of a substance that increases salt and water retention in your body.
Most important fact about Zestril
If you have high blood pressure, you must take Zestril regularly for it to be effective. Since blood pressure declines gradually, it may be several weeks before you get the full benefit of Zestril; and you must continue taking it even if you are feeling well. Zestril does not cure high blood pressure; it merely keeps it under control.
How should you take Zestril?
Zestril can be taken with or without food. Take it exactly as prescribed. Stopping Zestril suddenly could cause your blood pressure to rise.
--If you miss a dose...
Take the forgotten dose as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Never take 2 doses at the same time.
--Storage instructions...
Store at room temperature, with the container sealed and dry. Avoid excessive heat or freezing cold.
What side effects may occur?
Side effects cannot be anticipated. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Zestril.
• More common side effects may include:
Chest pain, cough, diarrhea, dizziness, headache, low blood pressure
Why should Zestril not be prescribed?
If you are sensitive to or have ever had an allergic reaction to Zestril or other ACE inhibitors such as Capoten, you should not take Zestril. You should also avoid Zestril if you suffered angioedema (swelling of the face, lips, tongue, throat, arms, or legs) during previous treatment with an ACE inhibitor, or have a tendency to develop the condition for any other reason. Make sure your doctor is aware of any drug reactions you have experienced.
Special warnings about Zestril
If you develop a sore throat, fever, or swelling of your face, lips, tongue, throat, arms or legs; or have difficulty swallowing or breathing, you should contact your doctor immediately. You may have a serious side effect of the drug and need emergency treatment.
If you develop abdominal pain with or without nausea and vomiting, contact your doctor. ACE inhibitors such as Zestril have been known to cause intestinal swelling.
If you are being given bee or wasp venom to guard against future reactions, you may have a severe reaction to Zestril.
If you have congestive heart failure or other heart problems, a kidney disorder, or a connective tissue disease such as lupus, you should use Zestril with caution. Your doctor may perform periodic blood tests while you are taking Zestril.
If you are taking Zestril, a complete assessment of your kidney function should be done and kidney function should continue to be monitored. Zestril is used with great caution after a heart attack if the patient also has kidney problems.
This drug also should be used with caution if you are on dialysis. There have been reports of extreme allergic reactions during dialysis in people taking ACE inhibitor medications such as Zestril.
If you are taking high doses of a diuretic (water pill) and Zestril, you may develop excessively low blood pressure. This problem is also more likely if you are being treated for heart failure.
Zestril may cause some people to become dizzy, light-headed, or faint, especially if they have heart failure or are taking a water pill at the same time. Do not drive, operate dangerous machinery, or participate in any hazardous activity that requires full mental alertness until you are certain Zestril does not have this effect on you.
If you develop chest pain, sore throat, fever, and chills, contact your doctor for medical attention. It could indicate a more serious condition.
If your skin and the whites of your eyes turn yellow, stop taking the medication and contact your doctor.
Avoid salt substitutes that contain potassium. Limit your consumption of potassium-rich foods such as bananas, prunes, raisins, orange juice, and whole and skim milk. Ask your doctor for advice on how much of these foods to consume.
Excessive sweating, dehydration, severe diarrhea, or vomiting could cause you to lose too much water and cause your blood pressure to drop dangerously.
Possible food and drug interactions when taking Zestril
If Zestril is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Zestril with any of the following:

Nonsteroidal anti-inflammatory drugs such as indomethacin (Indocin)
Lithium (Lithonate, Eskalith)
Potassium preparations such as K-Phos and Micro-K
Water pills such as HydroDIURIL and Lasix, and others that leave potassium in the body, such as Aldactone and Midamor
Special information if you are pregnant or breastfeeding
If it is taken during the final 6 months of pregnancy, Zestril can cause birth defects, prematurity, and death in the fetus and newborn. If you are pregnant or plan to become pregnant and are taking Zestril, contact your doctor immediately to discuss the potential hazard to your unborn child. Zestril may appear in breast milk and could affect a nursing infant. If Zestril is essential to your health, your doctor may advise you to discontinue breastfeeding until your treatment with Zestril is finished.
Recommended dosage
ADULTS
High Blood Pressure
For people not on water pills (diuretics), the initial starting dose is usually 10 milligrams, taken 1 time a day. Your doctor will increase the dosage until your blood pressure is under control. The long-term dosage usually ranges from 20 to 40 milligrams a day, taken in a single dose.
Diuretic use should, if possible, be stopped before using Zestril. If not, your physician may give an initial dose of 5 milligrams under supervision before any further medication is prescribed.
People with kidney disorders must be carefully monitored, and dosages will be adjusted to the individual's needs, depending on kidney function.
Heart Failure
For this condition, Zestril is usually prescribed along with diuretics and digitalis. The recommended starting dose is 5 milligrams once a day, with the first dose taken under your doctor's supervision. The doctor may increase the dose by up to 10 milligrams at intervals of no less than 2 weeks. Typical long-term dosages range from 5 to 40 milligrams taken once a day.
Heart Attack
The usual dose is 5 milligrams within the first 24 hours after a heart attack, then 5 milligrams 24 hours later, 10 milligrams 48 hours later, and, finally, 10 milligrams once a day for 6 weeks. If low blood pressure is a problem, the doctor may recommend a lower dosage.
CHILDREN 6 YEARS OR OLDER
High Blood Pressure
The usual starting dose is 0.07 milligrams per day up to a total of 5 milligrams per day.
Zestril is not recommended in children younger than 6 years old or in children with poor kidney function.
OLDER ADULTS
The physician will adjust the dosage carefully, according to the individual's needs.
Overdosage
Any medication taken in excess can cause symptoms of overdose. If you suspect an overdose, seek medical attention immediately.
A severe drop in blood pressure is the primary sign of a Zestril overdose.