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URL of this page: https://medlineplus.gov/druginfo/meds/a601076.html

Methyldopa and Hydrochlorothiazide

pronounced as (meth ill doe' pa) (hye droe klor oh thye' a zide)

Why is this medication prescribed?

The combination of methyldopa and hydrochlorothiazide is used to treat high blood pressure. Methyldopa works by relaxing the blood vessels so that blood can flow more easily through the body. Hydrochlorothiazide helps to lower blood pressure by eliminating unneeded water and salt from the body.

High blood pressure is a common condition and when not treated, 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?

This medication comes as a tablet to take by mouth. It usually is taken two or three times a day. To help you remember to take methyldopa and hydrochlorothiazide, take it around the same times 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 methyldopa and hydrochlorothiazide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

This medication controls high blood pressure but does not cure it. Continue to take methyldopa and hydrochlorothiazide even if you feel well. Do not stop taking methyldopa 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 methyldopa and hydrochlorothiazide,

  • tell your doctor and pharmacist if you are allergic to methyldopa, hydrochlorothiazide, sulfa medications, any other medications, or any of the ingredients in methyldopa and hydrochlorothiazide tablets. Ask your doctor or pharmacist for a list of the ingredients.
  • tell your doctor if you are taking a monoamine oxidase (MAOs) inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate). Your doctor will probably tell you not to take methyldopa and hydrochlorthiazide.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: cholestyramine (Prevalite), digoxin (Lanoxin), haloperidol (Haldol), levodopa (in Sinemet, in Stalevo), lithium (Lithobid), medications for diabetes, prednisone (Rayos), probenecid (Probalan, in Col-Probenecid), and tolbutamide. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • if you are taking iron supplements or vitamins containing iron, do not take them at the same time as you take methyldopa and hydrochlorthiazide. Ask your doctor how long you should wait after taking these supplements before you take methyldopa.
  • tell your doctor if you have or have ever had kidney or liver disease, diabetes, gout, or high blood cholesterol.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking methyldopa and hydrochlorothiazide, call your doctor.
  • talk to your doctor about the risks and benefits of taking methyldopa and hydrochlorothiazide if you are 65 years of age or older. Older adults should not usually take methyldopa and hydrochlorothiazide because it is not as safe as other medications that can be used to treat the same condition.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking methyldopa and hydrochlorothiazide.
  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery for 48-72 hours after you begin to take this medication or after your dose is increased.
  • ask your doctor about the safe use of alcohol while you are taking methyldopa and hydrochlorothiazide. Alcohol can make the side effects from methyldopa and hydrochlorothiazide worse.

What special dietary instructions should I follow?

Your doctor may prescribe a low-salt or low-sodium diet. Follow these 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?

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

  • dark urine
  • frequent urination
  • dry mouth
  • headache
  • upset stomach
  • vomiting
  • loss of appetite
  • diarrhea
  • gas
  • rash

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

  • extreme tiredness
  • muscle weakness or cramps
  • unexplained fever
  • yellowing of the skin or eyes
  • trouble breathing
  • swollen ankles or feet

This medication may cause other side effects. Call your doctor if you have any unusual problems while you are 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 (http://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 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

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.

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 methyldopa and hydrochlorothiazide.

To relieve dry mouth caused by methyldopa and hydrochlorothiazide, chew gum or suck sugarless hard candy.

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

  • Aldoril®

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

Last Revised - 05/15/2019