Captopril is used in adults alone or in combination with other medications to treat high blood pressure (hypertension) and congestive heart failure.

Captopril is also used to improve survival and reduce the risk of heart failure after a heart attack in patients with a heart condition called left ventricular hypertrophy (enlargement of the walls of the left side of the heart). Captopril is also used to treat kidney disease (nephropathy) caused by diabetes in patients with type 1 diabetes and retinopathy (eye disease).

Captopril belongs to a class of medications called angiotensin-converting enzyme (ACE) inhibitors. It decreases certain chemicals that tighten the blood vessels, so blood flows more smoothly and the heart can pump blood more efficiently.

Do not use captopril if you are pregnant. Stop using captopril and tell your doctor right away if you become pregnant.

If you have diabetes, do not use captopril together with any medication that contains aliskiren (Amturnide, Tekturna, Tekamlo).

Tell your doctor about all your other medicines. Some drugs should not be used with captopril.

Take captopril exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Take on an empty stomach, at least 1 hour before a meal.

Call your doctor if you have ongoing vomiting or diarrhea, or if you are sweating more than usual. You can easily become dehydrated while taking captopril. This can lead to very low blood pressure, an electrolyte imbalance, or kidney failure.

Your blood pressure will need to be checked often, and you may need frequent blood tests.

captopril may cause false results on a urine test. Tell the laboratory staff that you use captopril.

Tell your doctor if you have a planned surgery.

If you have high blood pressure, keep using this medicine even if you feel well. High blood pressure often has no symptoms.

Store tightly closed at room temperature, away from moisture and heat.

Usual Adult Dose for Hypertension:

Initial dose: 25 mg orally 2 to 3 times a day one hour before meals

Maintenance dose: May increase every 1 to 2 weeks up to 50 mg orally three times a day. If blood pressure remains uncontrolled after 1 to 2 weeks at this dose, add a thiazide diuretic (loop diuretic if severe renal impairment exists) and titrate to its highest usual antihypertensive dose before further increases of captopril.

Maximum dose: 450 mg/day

Usual Adult Dose for Congestive Heart Failure:

Initial dose: 25 mg orally three times a day (6.25 to 12.5 mg orally three times a day if hypotensive, hyponatremic, or hypovolemic)

Target maintenance dose: 50 mg orally three times a day for at least two weeks to ensure a satisfactory response

Maximum dose: 450 mg/day

Comments:
-Most patients experience satisfactory clinical improvement at 50 or 100 mg orally three times a day.
-Should generally be used in conjunction with a diuretic and digitalis.

Usual Adult Dose for Left Ventricular Dysfunction:

Initial dose: 6.25 mg orally once as early as three days post-myocardial infarction, followed by 12.5 mg orally three times a day; increase to 25 mg orally three times a day over the next several days, and then increase to target dose over the next several weeks as tolerated.

Target maintenance dose: 50 mg orally three times a day

Use: To improve survival following myocardial infarction in clinically stable patients with left ventricular dysfunction manifested as an ejection fraction of 40% or less and to reduce the incidence of overt heart failure and subsequent hospitalizations for congestive heart failure in these patients.

Usual Adult Dose for Diabetic Nephropathy:

25 mg orally three times a day

Comments: Other antihypertensives may be used in conjunction with this drug if additional blood pressure reduction is required.

Use: Treatment of diabetic nephropathy (proteinuria greater than 500 mg/day) in patients with type I insulin-dependent diabetes mellitus and retinopathy.

Usual Adult Dose for Hypertensive Emergency:

25 mg orally 2 to 3 times a day; continue diuretic therapy and stop other antihypertensives upon initiation of this drug; may increase dose every 24 hours or less until satisfactory blood pressure or maximum dose is reached.

You should not use this medicine if you are allergic to captopril or to any other ACE (angiotensin converting enzyme) inhibitor such as benazepril, fosinopril, enalapril, lisinopril, moexipril, perindopril, quinapril, ramipril, or trandolapril.

If you have diabetes, do not take captopril with any medication that contains aliskiren (a blood pressure medicine).

Do not take captopril within 36 hours before or after taking medicine that contains sacubitril (such as Entresto).

To make sure captopril is safe for you, tell your doctor if you have ever had:

• heart failure, heart problems;

• severe allergic reaction such as angioedema;

• stomach pain;

• low blood pressure;

• low white blood cell counts;

• a connective tissue disease such as Marfan syndrome, Sjogren's syndrome, lupus, scleroderma, or rheumatoid arthritis;

• if you are on a low-salt diet;

• to take medicines that weaken the immune system such as cancer medicine, steroids, and medicines to prevent organ transplant rejection;

• diabetes;

• liver disease; or

• kidney disease (or if you are on dialysis).

You may also need to avoid taking captopril with aliskiren if you have kidney disease.

Stop using this medicine and tell your doctor right away if you become pregnant. Captopril can cause injury or death to the unborn baby if you use the medicine during your second or third trimester.

Do not breastfeed.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Talk to your doctor before using salt substitutes containing potassium. If your doctor prescribes a low-salt or low-sodium diet, follow these instructions carefully.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Do not take potassium supplements or use salt substitutes, unless your doctor has told you to.

Avoid becoming overheated or dehydrated during exercise, in hot weather, or by not drinking enough fluids. Follow your doctor's instructions about the type and amount of liquids you should drink. In some cases, drinking too much liquid can be as unsafe as not drinking enough.

Avoid strenuous exercise if you are being treated for heart failure. Ask your doctor about your risk.

Get emergency medical help if you have signs of an allergic reaction to captopril: severe stomach pain, hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Captopril may cause serious side effects. Call your doctor at once if you have:

• chest pain, fast, slow, or uneven heart rate;

• a light-headed feeling, like you might pass out;

• heart problems - swelling, rapid weight gain, feeling short of breath;

• kidney problems - swelling, urinating less, feeling tired or short of breath;

• signs of infection - fever, chills, sore throat, body aches, unusual tiredness, loss of appetite, bruising or bleeding;

• high blood potassium - nausea, weakness, tingly feeling, chest pain, irregular heartbeats, loss of movement;

• low blood sodium - headache, confusion, problems with thinking or memory, weakness, feeling unsteady; or

• low white blood cell counts - fever, mouth sores, skin sores, sore throat, cough.

Common captopril side effects may include:

• cough;

• low blood pressure;

• flushing (sudden warmth, redness, or tingly feeling);

• low blood cell counts;

• decreased sense of taste; or

• mild skin itching or rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Captopril can harm your kidneys, especially if you also use certain medicines for infections, cancer, or osteoporosis.

Tell your doctor about all your other medicines, especially:

• a diuretic or "water pill" that may increase blood potassium such as spironolactone, triamterene, amiloride;

• NSAIDs (nonsteroidal anti-inflammatory drugs) - aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others;

• medicine to prevent organ transplant rejection such as temsirolimus, sirolimus, or everolimus; or

• heart or blood pressure medication.

This list is not complete. Other drugs may interact with captopril, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Keep all appointments with your doctor and the laboratory. Your blood pressure should be checked regularly to determine your response to captopril.

Captopril tablets may have a slight sulfur odor (like rotten eggs).

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.