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URL of this page: https://medlineplus.gov/druginfo/meds/a601034.html

Captopril and Hydrochlorothiazide

pronounced as (kap' toe pril) (hye droe klor oh thye' a zide)

IMPORTANT WARNING:

Do not take captopril and hydrochlorothiazide if you are pregnant. If you become pregnant while taking captopril and hydrochlorothiazide, call your doctor immediately. Captopril and hydrochlorothiazide may harm the fetus.

Why is this medication prescribed?

The combination of captopril and hydrochlorothiazide is used to treat high blood pressure. Captopril is in a class of medications called angiotensin-converting enzyme (ACE) inhibitors. It works by decreasing certain chemicals that tighten the blood vessels, so blood flows more smoothly. Hydrochlorothiazide is in a class of medications called diuretics ('water pills'). It works by causing the kidneys to get rid of unneeded water and salt from the body into the urine.

High blood pressure is a common condition, and when not treated it can cause damage to the brain, heart, blood vessels, kidneys, and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

How should this medicine be used?

The combination of captopril and hydrochlorothiazide comes as a tablet to take by mouth. It is usually taken once or twice a day on an empty stomach, 1 hour before meals. To help you remember to take captopril and hydrochlorothiazide, take it around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take captopril and hydrochlorothiazide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor may start you on a low dose of captopril and hydrochlorothiazide and gradually increase your dose, not more than once every 6 to 8 weeks.

Captopril and hydrochlorothiazide controls high blood pressure but does not cure it. Continue to take captopril and hydrochlorothiazide even if you feel well. Do not stop taking captopril and hydrochlorothiazide without talking to your doctor.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking captopril and hydrochlorothiazide,

  • tell your doctor and pharmacist if you are allergic to captopril (Capoten); hydrochlorothiazide (HCTZ; Microzide, Oretic); angiotensin-converting enzyme (ACE) inhibitors such as benazepril (Lotensin, in Lotrel), enalapril (Vasotec, in Vaseretic), fosinopril (Monopril), lisinopril (in Prinzide, in Zestoretic), moexipril (Univasc, in Uniretic), perindopril (Aceon), quinapril (Accupril, in Accuretic, in Quinaretic), ramipril (Altace), and trandolapril (Mavik, in Tarka); sulfa drugs; any other medications; or any of the ingredients in captopril and hydrochlorothiazide tablets. Ask your pharmacist for a list of the ingredients.
  • tell your doctor or pharmacist if you are taking valsartan and sacubitril (Entresto) or if you have stopped taking it within the last 36 hours. Your doctor will probably tell you not to take captopril and hydrochlorothiazide, if you are also taking valsartan and sacubitril. Also, tell your doctor if you have diabetes and you are taking aliskiren (Tekturna, in Amturnide, in Tekamlo, in Tekturna HCT). Your doctor will probably tell you not to take captopril and hydrochlorothiazide if you have diabetes and you are also taking aliskiren.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking while taking captopril and hydrochlorothiazide. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • The following nonprescription products may interact with captopril and hydrochlorothiazide: aspirin and other nonsteroidal anti-inflammatory medications (NSAIDs) such as ibuprofen (Advil, Motrin), and naproxen (Aleve, Naprosyn); potassium supplements. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking captopril and hydrochlorothiazide. Do not start any of these medications while taking captopril and hydrochorothiazide without discussing with your healthcare provider.
  • tell your doctor if you have or have ever had lupus; scleroderma (a condition in which extra tissue grows on the skin and some organs); heart failure; diabetes; allergy; asthma; or liver or kidney disease.
  • tell your doctor if you are breastfeeding.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking captopril and hydrochlorothiazide.
  • ask your doctor about the safe use of alcoholic beverages while you are taking captopril and hydrochlorothiazide. Alcohol can worsen the side effects of captopril and hydrochlorothiazide.
  • 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.

What special dietary instructions should I follow?

Talk to your doctor before using salt substitutes containing potassium. If your doctor prescribes a low-sodium (low-salt) diet, follow those directions carefully.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Captopril and hydrochlorothiazide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • cough
  • dizziness or lightheadedness
  • taste changes
  • rash
  • itching

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

  • swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
  • hoarseness
  • difficulty breathing or swallowing
  • fever, sore throat, chills, and other signs of infection
  • yellowing of the skin or eyes
  • dry mouth
  • thirst
  • weakness
  • lack of energy
  • restlessness
  • muscle pains or cramps
  • infrequent urination
  • upset stomach
  • vomiting
  • fainting
  • chest pain
  • rapid, pounding, or irregular heartbeat

Captopril and hydrochlorothiazide may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

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 (https://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. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • drowsiness
  • coma
  • difficulty breathing
  • stomach pain

What other information should I know?

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

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking captopril and hydrochlorothiazide.

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.

Brand names

  • Capozide®

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 06/20/2024