Quinapril is used alone or in combination with other medications to treat high blood pressure. It is used in combination with other medications to treat heart failure. It works by decreasing certain chemicals that tighten the blood vessels, so blood flows more smoothly and the heart can pump blood more efficiently.

Take quinapril exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Quinapril controls high blood pressure and heart failure but does not cure them. Continue to take quinapril even if you feel well. Do not stop taking quinapril without talking to your doctor.

Special precautions

Before taking quinapril,

• Tell your doctor and pharmacist if you are allergic to quinapril, or any other medicines.
• Tell your doctor and pharmacist if you are taking vitamins, nutritional supplements, and herbal products.
• tell your doctor if you have or have ever had heart, liver, or kidney disease; lupus; scleroderma; diabetes; or angioedema, a condition that causes difficulty swallowing or breathing and painful swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs.
• Tell your doctor if you plan to become pregnant or are breast-feeding.

• Do not take quinapril if you are pregnant. If you become pregnant while taking quinapril, call your doctor immediately. Quinapril may harm the fetus.

• If you are having surgery, including dental surgery, tell the doctor or dentist that you are taking quinapril.
• You should know that diarrhea, vomiting, not drinking enough fluids, and sweating a lot can cause a drop in blood pressure, which may cause lightheadedness and fainting.

Side effects

Quinapril may cause side effects:

• dizziness
• excessive tiredness
• cough
• upset stomach
• vomiting

Some side effects can be serious. The following symptoms are uncommon:

• swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• hoarseness
• difficulty breathing or swallowing
• yellowing of the skin or eyes
• fever, sore throat, chills, and other signs of infection
• chest pain
• lightheadedness
• fainting

Symptoms of overdose may include:

• lightheadedness
• fainting

Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly to determine your response to quinapril. Your doctor may order certain lab tests to check your body's response to quinapril.