Methyldopa and hydrochlorothiazide (Oral)
Generic Name: hydrochlorothiazide/methyldopa (meth-il-DOE-pa, hye-droe-klor-oh-THYE-a-zide)
Medically reviewed by Drugs.com. Last updated on Dec 22, 2020.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Alpha-Adrenergic Agonist/Thiazide Combination
Pharmacologic Class: Alpha-Adrenergic Agonist
Chemical Class: Thiazide
Uses for methyldopa and hydrochlorothiazide
Methyldopa and hydrochlorothiazide combination is used to treat high blood pressure (hypertension).
High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.
Methyldopa works by controlling nerve impulses along certain nerve pathways. As a result, it relaxes blood vessels so that blood passes through them more easily. Hydrochlorothiazide helps reduce the amount of water in the body by increasing the flow of urine. These actions help to lower blood pressure.
Methyldopa and hydrochlorothiazide is available only with your doctor's prescription.
Before using methyldopa and hydrochlorothiazide
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For methyldopa and hydrochlorothiazide, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to methyldopa and hydrochlorothiazide or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Although there is no specific information comparing use of methyldopa and hydrochlorothiazide in children with use in other age groups, it is not expected to cause different side effects or problems in children than it does in adults.
Dizziness or light-headedness, drowsiness, or signs of too much potassium loss may be more likely to occur in the elderly, who are more sensitive to the effects of methyldopa and hydrochlorothiazide.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.Methyldopa
Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking methyldopa and hydrochlorothiazide, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using methyldopa and hydrochlorothiazide 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 methyldopa and hydrochlorothiazide 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.
- Amtolmetin Guacil
- Arsenic Trioxide
- Choline Salicylate
- Flufenamic Acid
- Iobenguane I 131
- Mefenamic Acid
- Niflumic Acid
- Nimesulide Beta Cyclodextrin
- Salicylic Acid
- Sodium Salicylate
- Tiaprofenic Acid
- Tolfenamic Acid
Using methyldopa and hydrochlorothiazide 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.
- Aminolevulinic Acid
- Ferric Ammonium Citrate
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of methyldopa and hydrochlorothiazide. Make sure you tell your doctor if you have any other medical problems, especially:
- Angina (chest pain)—Methyldopa may worsen the condition.
- Type 2 diabetes mellitus—Hydrochlorothiazide may change the amount of diabetes medicine needed.
- Gout (history of)—Hydrochlorothiazide may increase the amount of uric acid in the blood, which can lead to gout.
- High cholesterol—Hydrochlorothiazide may raise cholesterol levels.
- Kidney disease—Effects of methyldopa and hydrochlorothiazide may be increased because of slower removal from the body. If severe, hydrochlorothiazide may not work.
- Liver disease—Effects of methyldopa may be increased because of slower removal from the body. If hydrochlorothiazide causes loss of too much water from the body, liver disease can become much worse.
- Lupus erythematosus (history of)—Hydrochlorothiazide may worsen the condition.
- Mental depression (history of)—Methyldopa can cause mental depression
- Pancreatitis (inflammation of the pancreas)
- Parkinson's disease—Methyldopa may worsen the condition.
- Pheochromocytoma—Methyldopa may interfere with tests for the condition. In addition, there have been reports of increased blood pressure.
Proper use of methyldopa and hydrochlorothiazide
In addition to the use of the medicine your doctor has prescribed, appropriate treatment for your high blood pressure may include weight control and care in the types of foods you eat, especially foods high in sodium. Your doctor will tell you which factors are most important for you. You should check with your doctor before changing your diet.
Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.
Remember that methyldopa and hydrochlorothiazide will not cure your high blood pressure but it does help control it. Therefore, you must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.
Methyldopa and hydrochlorothiazide may cause you to have an unusual feeling of tiredness when you begin to take it. You may also notice an increase in the amount of urine or in your frequency of urination. After taking the medicine for a while, these effects should lessen. In general, to keep the increase in urine from affecting your sleep:
- If you are to take a single dose a day, take it in the morning after breakfast.
- If you are to take more than one dose a day, take the last dose no later than 6 p.m., unless otherwise directed by your doctor.
However, it is best to plan your dose or doses according to a schedule that will least affect your personal activities and sleep. Ask your health care professional to help you plan the best time to take methyldopa and hydrochlorothiazide.
To help you remember to take your medicine, try to get into the habit of taking it at the same time each day.
The dose of methyldopa and hydrochlorothiazide will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of methyldopa and hydrochlorothiazide. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For treating high blood pressure:
- For oral dosage form (tablets):
- Adults: Two to four tablets a day, taken as a single dose or in divided doses.
- Children: Dose must be determined by your doctor.
- For oral dosage form (tablets):
If you miss a dose of methyldopa and hydrochlorothiazide, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Keep out of the reach of children.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Do not keep outdated medicine or medicine no longer needed.
Precautions while using methyldopa and hydrochlorothiazide
It is important that your doctor check your progress at regular visits to make sure that methyldopa and hydrochlorothiazide is working properly.
Do not take other medicines unless they have been discussed with your doctor. This especially includes over-the-counter (nonprescription) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, since they may tend to increase your blood pressure.
Methyldopa and hydrochlorothiazide may cause a loss of potassium from your body:
- To help prevent this, your doctor may want you to:
- eat or drink foods that have a high potassium content (for example, orange or other citrus fruit juices), or
- take a potassium supplement, or
- take another medicine to help prevent the loss of the potassium in the first place.
- It is very important to follow these directions. Also, it is important not to change your diet on your own. This is more important if you are already on a special diet (as for diabetes), or if you are taking a potassium supplement or a medicine to reduce potassium loss. Extra potassium may not be necessary and, in some cases, too much potassium could be harmful.
Check with your doctor if you become sick and have severe or continuing vomiting or diarrhea. These problems may cause you to lose additional water and potassium.
Before having any kind of surgery (including dental surgery) or emergency treatment, tell the medical doctor or dentist in charge that you are taking methyldopa and hydrochlorothiazide.
If you have a fever and there seems to be no reason for it, check with your doctor. This is especially important during the first few weeks you take methyldopa and hydrochlorothiazide since fever may be a sign of a serious reaction to methyldopa.
Methyldopa and hydrochlorothiazide may cause some people to become drowsy or less alert than they are normally. This is more likely to happen when you begin to take it or when you increase the amount of medicine you are taking. Make sure you know how you react to methyldopa and hydrochlorothiazide before you drive, use machines, or do anything else that could be dangerous if you are not alert.
Dizziness, light-headedness, or fainting may occur, especially when you get up from a lying or sitting position. Getting up slowly may help, but if the problem continues or gets worse, check with your doctor.
The dizziness, light-headedness, or fainting is also more likely to occur if you drink alcohol, stand for long periods of time, exercise, or if the weather is hot. Drinking alcoholic beverages may also make the drowsiness worse. While you are taking methyldopa and hydrochlorothiazide, be careful in the amount of alcohol you drink. Also, use extra care during exercise or hot weather or if you must stand for long periods of time.
For diabetic patients:
- Methyldopa and hydrochlorothiazide may raise blood sugar levels. While you are using methyldopa and hydrochlorothiazide, be especially careful in testing for sugar in your urine. If you have any questions about this, check with your doctor.
Methyldopa and hydrochlorothiazide may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.
Hydrochlorothiazide may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking methyldopa and hydrochlorothiazide:
- Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
- Wear protective clothing, including a hat. Also, wear sunglasses.
- Apply a sun block product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your health care professional.
- Apply a sun block lipstick that has an SPF of at least 15 to protect your lips.
- Do not use a sunlamp or tanning bed or booth.
If you have a severe reaction from the sun, check with your doctor
Before you have any medical tests, tell the doctor in charge that you are taking methyldopa and hydrochlorothiazide. The results of some tests may be affected by methyldopa and hydrochlorothiazide.
Methyldopa and hydrochlorothiazide side effects
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:
- Unexplained fever shortly after starting to take methyldopa and hydrochlorothiazide
Check with your doctor as soon as possible if any of the following side effects occur:
Signs and symptoms of too much potassium loss
- Dry mouth
- increased thirst
- irregular heartbeats
- muscle cramps or pain
- nausea or vomiting
- unusual tiredness or weakness
- weak pulse
- Mental depression or anxiety
- nightmares or unusually vivid dreams
- Cough or hoarseness
- 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
- lower back or side pain
- painful or difficult urination
- pale stools
- skin rash, hives, or itching
- stomach pain (severe) with nausea and vomiting
- tiredness or weakness after having taken methyldopa and hydrochlorothiazide 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:
- Dizziness or light-headedness when getting up from a lying or sitting position
- dryness of mouth
- Decreased sexual ability or interest in sex
- increased sensitivity of skin to sunlight (skin rash, itching, redness or other discoloration of skin or severe sunburn after exposure to sunlight)
- loss of appetite
- numbness, tingling, pain, or weakness in hands or feet
- slow heartbeat
- stuffy nose
- swelling of breasts or unusual milk production
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.
More about hydrochlorothiazide / methyldopa
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- During Pregnancy
- Dosage Information
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- Drug Interactions
- Pricing & Coupons
- En Español
- Drug class: antiadrenergic agents (central) with thiazides
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