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.
How should this medicine be used?
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.
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, Hydrodiuril, Microzide), benazepril (Lotensin), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace), trandolapril (Mavik), sulfa drugs, or any other medications.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any of the following: amphotericin B (Fungizone); anticoagulants ('blood thinners') such as warfarin (Coumadin); aspirin and other nonsteroidal anti-inflammatory medications (NSAIDs) such as indomethacin (Indocin); calcium supplements; cancer chemotherapy drugs; cholestyramine (Questran); colestipol (Colestid); digoxin (Lanoxin); insulin or oral medications for diabetes; lithium (Eskalith, Lithobid); medications for gout such as probenecid (Benemid) and sulfinpyrazone (Anturane); medications that suppress the immune system; methenamine (Mandelamine, Hiprex); monoamine oxidase (MAO) inhibitors, including phenelzine (Nardil) and tranylcypromine (Parnate); nitrates such as isosorbide dinitrate (Isordil), isosorbide mononitrate (Imdur, ISMO, Monoket), and nitroglycerin (Nitrogard, Nitrolingual, Nitrostat, others); oral steroids such as dexamethasone (Decadron, Dexone), methylprednisolone (Medrol), and prednisone (Deltasone); other diuretics; other medications for high blood pressure; pain medications; phenobarbital (Luminal, Solfoton); and potassium supplements. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had lupus; scleroderma; heart failure; diabetes; allergy; asthma; or liver or kidney disease.
- tell your doctor if you plan to become pregnant or are breast-feeding.
- 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.
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:
- dizziness or lightheadedness
- taste changes
- rash and/or itching
Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:
- swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
- difficulty breathing or swallowing
- fever, sore throat, chills, and other signs of infection
- yellowing of the skin or eyes
- dry mouth
- lack of energy
- muscle pains or cramps
- infrequent urination
- upset stomach
- 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.
What storage conditions are needed for this medicine?
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). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
Symptoms of overdose may include:
- 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.