Methyldopa is an oral tablet that's used to treat high blood pressure. It belongs to a group of medications called alpha-2 adrenergic receptor agonists. Because it doesn't last long in your body, it must be taken a few times a day. Methyldopa is preferred over other medications for treating high blood pressure during pregnancy. Some potential side effects include sleepiness, headache, and weakness.
Methyldopa is an alpha-2 adrenergic receptor agonist. It works by signaling the brain to cause your blood vessels to relax. This makes it easier for blood to flow and lowers your blood pressure.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
Fever, shortly after starting to take this medicine
Check with your doctor as soon as possible if any of the following side effects occur:
More common
Swelling of feet or lower legs
Rare
Dark or amber urine
diarrhea or stomach cramps (severe or continuing)
fever, chills, troubled breathing, and fast heartbeat
general feeling of discomfort or illness or weakness
joint pain
pale stools
skin rash or itching
stomach pain (severe) with nausea and vomiting
tiredness or weakness after having taken this medicine for several weeks (continuing)
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Drowsiness
dryness of mouth
headache
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Dose can be adjusted based on response
Safe to use if you're pregnant
Comes in two different strengths
Available as a lower-cost generic
Has many possible side effects
Must be taken 2 to 4 times a day
Not a first-choice option for treating high blood pressure
Not safe if you have liver problems
You can take methyldopa with or without food. Nausea is a possible side effect of this medication, so if this happens to you, take your doses with something to eat.
For the most consistent results, take methyldopa at the same times every day.
It's common to feel sleepy and dizzy when starting methyldopa or after a dose change. These side effects usually improve after a week or two on the same dose. Be careful changing positions during this time, as doing so too quickly can cause you to fall. Let your prescriber know if the side effects are bothersome.
Methyldopa commonly causes dry mouth. There are mouthwashes, lozenges, and sprays that can help lessen this feeling. Ask your pharmacist if you need help selecting one of these products.
Let your prescriber know if you're taking any antidepressants or medications for Parkinson's disease. Some of these medications interact with methyldopa and can cause dangerously high blood pressure.
Methyldopa can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: History of or current liver problems
Although rare, methyldopa can cause serious liver problems. In some cases, this can be life-threatening. Because of this, people with liver problems shouldn't take this medication. Be sure to attend all follow-up appointments and complete any blood tests ordered so your care team can track your liver function. If you experience any unusual vomiting, pale stools, dark urine, stomach pain, or yellowing of your skin and whites of your eyes, seek medical attention right away.
Risk factors: Positive Coombs test | Using methyldopa for a long time
Although very rare, taking methyldopa for a long time can cause a serious condition called hemolytic anemia. This life-threatening problem causes your body to destroy your red blood cells faster than they can be replaced. This typically happens between 6 and 12 months after starting methyldopa. If you're going to be taking this medication for a long time, you'll have to get regular blood tests done to watch for early signs of this condition.
Rarely, methyldopa can lower the number of white blood cells and platelets in your body. White blood cells help your body fight infections, and without enough of them, you can get sick more easily and take longer to recover. Platelets help your blood clot to stop bleeding. You'll have to have blood tests done regularly while you're taking methyldopa to make sure your blood cells are at a normal level. If you experience changes in your blood cells, know that it's reversible. These side effects will go away once you stop taking the medication.
Adults: The typical starting dose is 250 mg by mouth 2 to 3 times a day. This can be raised to a maximum of 3,000 mg total per day, which would be split into 2 to 4 smaller doses taken throughout the day.
Children: The typical starting dose is 10 mg/kg of body weight by mouth total per day. This total dose will be split up into 2 to 4 smaller doses taken throughout the day. This can be raised to a maximum of 65 mg/kg of body weight or 3,000 mg per day, whichever is less.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Liver problems
Also taking a monoamine oxidase inhibitor (MAOI)
Chest pain (angina)
High blood pressure (hypertension) - extended-release tablets only
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