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Methyldopa - Oral

Pronunciation: METH-il-DOE-pa

Common Brand Name(s): Aldomet

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Uses

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.

How To Use

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. Keep 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).

Side Effects

Dizziness, lightheadedness, drowsiness, headache, stuffy nose, and weakness may occur as your body adjusts to the medication. If any of these effects last or get worse, 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.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

  • fainting
  • muscle spasms/uncontrolled muscle movements
  • missed/stopped periods
  • decreased sexual desire/ability
  • increased breast size (in men)
  • mental/mood changes (such as depression)
  • symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain)

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:

  • nausea/vomiting that doesn't stop
  • unusual tiredness
  • fast heartbeat
  • unexplained fever
  • dark urine
  • severe stomach/abdominal pain
  • yellowing eyes/skin

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

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. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

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.

This medication passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.

Drug Interactions

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, metaxalone, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, 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, marijuana (cannabis), antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and opioid pain relievers (such as codeine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

Some products have ingredients that could raise your blood pressure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen).

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.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness/dizziness.

Notes

Do not share this medication with others.

Lab and/or medical tests (such as hematocrit/hemoglobin, complete blood count, Coombs test, liver function) should be done while you are taking this medication. Keep all medical and lab appointments. 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.

Missed Dose

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. Take your next dose at the regular time. Do not double the dose to catch up.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

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.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.