This medication is used alone or with other medications to treat high blood pressure (hypertension). Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems. Methyldopa works by relaxing blood vessels so blood can flow more easily.
Take this medication by mouth with or without food as directed by your doctor, usually 2 to 4 times daily. Start this medication or any new dose increase in the evening to decrease the risk of side effects. Also, if the doses of this medication are not equal, take the larger dose at bedtime.
The dosage is based on your medical condition and response to treatment.
Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day. It is important to continue taking this medication even if you feel well. Most people with high blood pressure do not feel sick.
When used for a long time, this medication may not work as well and may require different dosing or an additional medication. Talk with your doctor if this medication stops working well (such as your blood pressure readings remain high or increase).
Dizziness, lightheadedness, drowsiness, headache, stuffy nose, and weakness may occur as your body adjusts to the medication. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.
Tell your doctor right away if you have any serious side effects, including: swelling ankles/feet, unexplained/sudden weight gain, fainting, muscle spasms/uncontrolled muscle movements, missed/stopped periods, decreased sexual desire/ability, increased breast size (in men), mental/mood changes (such as depression).
Methyldopa has rarely caused very serious (rarely fatal) liver disease or low red blood cell count (anemia). Tell your doctor right away if you develop any symptoms of liver disease or anemia, including: unusual tiredness, fast heartbeat, unexplained fever, dark urine, persistent nausea/vomiting, severe stomach/abdominal pain, yellowing eyes/skin.
In the US -
Before taking methyldopa, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease (such as hepatitis, cirrhosis), low red blood cell count (anemia), heart failure, pheochromocytoma, a certain genetic condition (glucose-6-phosphate dehydrogenase deficiency).
This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Older adults may be more sensitive to the side effects of this medication, especially dizziness (more likely when standing up), fainting, or depression. Dizziness and fainting can increase the risk of falling.
Tell your doctor if you are pregnant before using this medication.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: iron products (such as ferrous sulfate, ferrous gluconate), lithium.
Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before treatment with this medication. Ask your doctor when to start or stop taking this medication.
Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine).
Check the labels on all your medicines (such as cough-and-cold products, diet aids, or NSAIDs such as ibuprofen, naproxen) because they may contain ingredients that could cause drowsiness or increase your blood pressure. Ask your pharmacist for more details.
This medication may interfere with certain laboratory tests (including urine catecholamine test), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness/dizziness.
Do not share this medication with others.
Laboratory and/or medical tests (such as hematocrit/hemoglobin, complete blood count, Coombs test, liver function) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
Lifestyle changes such as stress reduction programs, exercise, and dietary changes may increase the effectiveness of this medicine. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.
Check your blood pressure regularly while taking this medication. Learn how to monitor your own blood pressure at home, and share the results with your doctor.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised December 2013. Copyright(c) 2013 First Databank, Inc.
With WebMD's Medicine Cabinet, you can check interactions with drugs.Go to medicine cabinet