Know the basics
What is methyldopa used for?
Methyldopa lowers blood pressure by decreasing the levels of certain chemicals in your blood. This allows your blood vessels (veins and arteries) to relax (widen) and your heart to beat more slowly and easily.
Methyldopa is used to treat hypertension (high blood pressure).
Methyldopa may also be used for purposes not listed in methyldopa guide.
How should I take methyldopa?
Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.
Shake the oral suspension (liquid) well just before you measure a dose. Measure the liquid with a special dose measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose measuring device, ask your pharmacist for one.
Keep using this medicine as directed, even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure methyldopa for the rest of your life.
Methyldopa can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using methyldopa.
If you need surgery or a blood transfusion, tell your caregivers ahead of time that you are using methyldopa.
Your blood pressure will need to be checked often. To be sure methyldopa is not causing harmful effects, your liver function may need to be tested. Visit your doctor regularly.
Do not stop taking methyldopa without first talking to your doctor. Stopping suddenly may make your condition worse.
How do I store methyldopa?
Methyldopa is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store methyldopa in the bathroom or the freezer. There may be different brands of methyldopa that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.
You should not flush methyldopa down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard methyldopa when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.
Know the precautions & warnings
What should I know before using methyldopa?
Before taking methyldopa,
- Tell your doctor and pharmacist if you are allergic to methyldopa, any other medications, sulfites, or any of the ingredients in methyldopa tablets or liquid. 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.
- 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: haloperidol (haldol), levodopa (in sinemet, in stalevo), lithium (lithobid), other medications for high blood pressure, and tolbutamide. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- Do not take with iron supplements or vitamins containing iron.
- Tell you doctor if you have or have ever had kidney or liver disease, including hepatitis or cirrhosis.
- Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking methyldopa, call your doctor.
- Talk to your doctor about the risks of taking methyldopa if you are 65 years of age or older. Older adults should not usually take methyldopa 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.
- You should know that methyldopa may make you drowsy. Do not drive a car or operate machinery for 48-72 hours after you begin to take methyldopa or after your dose is increased.
Is it safe to take methyldopa during pregnancy or breast-feeding?
There are no adequate studies in women for determining risk when using methyldopa during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking methyldopa. Methyldopa is pregnancy risk category B according to the US Food and Drug Administration (FDA).
FDA pregnancy risk category reference below:
- A=No risk,
- B=No risk in some studies,
- C=There may be some risk,
- D=Positive evidence of risk,
Know the side effects
What are the side effects of methyldopa?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
- Slow heart rate;
- Pale or yellowed skin, fever, confusion or weakness;
- Nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
- Skin rash, bruising, severe tingling, numbness, pain, muscle weakness;
- Feeling short of breath, even with mild exertion;
- Swelling in your hands, ankles, or feet;
- Easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
- Muscle movements you cannot control.
Less serious side effects may include:
- Weight gain;
- Drowsiness, dizziness, weakness;
- Joint pain or swelling, muscle pain;
- Dry mouth;
- Vomiting, stomach pain;
- Swollen or “black” tongue;
- Constipation, diarrhea, bloating, gas;
- Depressed mood, unusual thoughts, nightmares;
- Numbness or tingly feeling;
- Stuffy nose;
- Missed menstrual periods;
- Breast swelling or discharge.
Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.
Know the interactions
What drugs may interact with methyldopa?
Methyldopa may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval, especially:
- Ferrous gluconate, a type of iron (Ferate, Fergon);
- Ferrous sulfate, a type of iron (Feosol, Fer-in-Sol, Feratab, and others);
- Lithium (Eskalith, Lithobid);
- Any other blood pressure medications.
Does food or alcohol interact with methyldopa?
Methyldopa may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using methyldopa.
What health conditions may interact with methyldopa?
Methyldopa may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have , especially:
- Angina (chest pain).
- Parkinson’s disease—Methyldopa may make these conditions worse.
- Kidney disease.
- Liver disease—Effects of methyldopa may be increased because of slower removal from the body.
- Mental depression (history of)—Methyldopa can cause mental depression.
- Pheochromocytoma—Methyldopa may interfere with tests for the condition; in addition, there have been reports of increased blood pressure.
- If you have taken methyldopa in the past and developed liver problems.
Understand the dosage
The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using methyldopa.
What is the dose of methyldopa for an adult?
Usual Adult Dose for Hypertension
- Initial dose: 250 mg orally 2-3 times a day or 250 to 500 mg IV over 30 to 60 minutes every 6 hours, up to a maximum of 3 g/day.
- Maintenance dose: 500 mg to 2 g orally divided in 2 to 4 doses, up to a maximum of 3 g/day.
Usual Adult Dose for Hypertensive Emergency
- 250 to 500 mg IV over 30 to 60 minutes every 6 hours up to a maximum of 1 g every 6 hours or 4 g/day. Switch to the oral route at the same dosage once blood pressure is under control.
What is the dose of methyldopa for a child?
The dosage has not been established in pediatric patients. It may be unsafe for your child. It is always important to fully understand the safety of the drug before using. Please consult with your doctor or pharmacist for more information.
How is methyldopa available?
Methyldopa is available in the following dosage forms and strengths:
- Tablet, Oral: 250 mg, 500 mg.
- Solution, Injection: 50 mg/mL.
What should I do in case of an emergency or overdose?
In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.
What should I do if I miss a dose?
If you miss a dose of methyldopa, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Review Date: May 30, 2016 | Last Modified: January 4, 2017
Methyldopa. https://www.drugs.com/mtm/methyldopa.html. Accessed June, 30, 2016.
Methyldopa. http://www.everydayhealth.com/drugs/methyldopa. Accessed June, 30, 2016.
Methyldopa. http://www.mayoclinic.org/drugs-supplements/methyldopa-oral-route-intravenous-route/description/drg-20067791. Accessed June, 30, 2016.