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- Hydrochlorothiazide oral tablet is only available as a generic drug.
- Hydrochlorothiazide comes as a tablet or capsule that you take by mouth.
- Hydrochlorothiazide oral tablet is used to treat high blood pressure, and swelling caused by heart failure, liver damage, and certain medications.
Hydrochlorothiazide is a prescription drug. It comes as a tablet or capsule that you take by mouth.
Hydrochlorothiazide oral tablet is available in a generic form only. Generic drugs usually cost less than brand-name drugs.
Why it’s used
Hydrochlorothiazide is used to treat high blood pressure. It’s also used to treat swelling that’s caused by heart failure, liver damage (cirrhosis), and taking medications called corticosteroids or estrogens. It may also help treat swelling that’s caused by kidney problems.
This drug may be used alone or in combination with other drugs.
How it works
Hydrochlorothiazide belongs to a class of drugs called thiazide diuretics. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.
It isn’t known exactly how hydrochlorothiazide works. It’s thought that it works to remove excess salt and water from your body. This action keeps your heart from working as hard to pump blood, which lowers blood pressure and reduces swelling.
Hydrochlorothiazide can cause mild or serious side effects. The following list contains some of the key side effects that may occur while taking hydrochlorothiazide. This list does not include all possible side effects.
For more information on the possible side effects of hydrochlorothiazide, or tips on how to deal with a troubling side effect, talk with your doctor or pharmacist.
More common side effects
The more common side effects that can occur with hydrochlorothiazide include:
- blood pressure that’s lower than normal (especially when standing up after sitting or lying down)
- dizziness
- headache
- weakness
- erectile dysfunction (trouble getting or keeping an erection)
- tingling in your hands, legs, and feet
These effects may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.
Serious side effects
Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:
- severe skin reactions such as Stevens-Johnson syndrome and exfoliative dermatitis, with symptoms such as:
- painful skin rash
- skin peeling and blisters
- fever
- mouth sores
- kidney failure, with symptoms such as:
- weakness
- shortness of breath
- tiredness
- confusion
- abnormal heart rate or chest pain
- producing less urine than normal
- increased swelling in your legs, ankles, or feet
- blurred vision, with symptoms such as:
Hydrochlorothiazide oral tablet can interact with several other medications. Different interactions can cause different effects. For instance, some can interfere with how well a drug works, while others can cause increased side effects.
Below is a list of medications that can interact with hydrochlorothiazide. This list does not contain all drugs that may interact with hydrochlorothiazide.
Before taking hydrochlorothiazide, be sure to tell your doctor and pharmacist about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.
If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
Barbiturates
If you take these drugs with hydrochlorothiazide, your blood pressure may be lowered too much. You may have symptoms such as feeling dizzy when you stand up after sitting or lying down. Examples of these drugs include:
- phenobarbital
- pentobarbital
Lithium
In general, lithium
Blood pressure drugs
Taking hydrochlorothiazide with other blood pressure medications can make your blood pressure drop too low. Examples of these drugs include:
- angiotensin-converting enzyme (ACE) inhibitors, such as:
- lisinopril
- fosinopril
- enalapril
- angiotensin receptor blockers (ARBs), such as:
- losartan
- valsartan
- candesartan
- beta-blockers, such as:
- atenolol
- metoprolol
- bisoprolol
- calcium channel blockers, such as:
- amlodipine
- verapamil
- diltiazem
Cholesterol-lowering drugs
Taking hydrochlorothiazide with certain drugs that lower cholesterol levels may make hydrochlorothiazide less effective. This means it may not work as well to treat your blood pressure or swelling. Examples of these cholesterol drugs include:
Corticosteroids
Hydrochlorothiazide can lower your electrolyte levels. Taking corticosteroids with hydrochlorothiazide can cause further loss of electrolytes (especially potassium). Low potassium levels can lead to constipation, fatigue, muscle breakdown, and weakness. Examples of these drugs include:
- prednisone
- methylprednisolone
Diabetes drugs
Hydrochlorothiazide can cause high blood sugar levels. If you take hydrochlorothiazide with diabetes drugs, your doctor may increase your dosage of your diabetes medications. Examples of these drugs include:
- insulin
- oral diabetes drugs, such as:
- metformin
- glimepiride
- pioglitazone
- sitagliptin
Narcotics
Taking hydrochlorothiazide with narcotics can make your blood pressure drop too low. You may have symptoms such as feeling dizzy when you stand up after sitting or lying down. Examples of these drugs include:
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Taking NSAIDs with hydrochlorothiazide can make hydrochlorothiazide less effective. This means it may not work as well to treat your blood pressure or swelling.
If you’re taking an NSAID with hydrochlorothiazide, your doctor will closely monitor you. Examples of these drugs include:
Muscle relaxant
Taking hydrochlorothiazide with tubocurarine,
The hydrochlorothiazide dosage your doctor prescribes will depend on several factors. These include:
- the type and severity of the condition you’re using hydrochlorothiazide to treat
- your age
- the form of hydrochlorothiazide you take
- other medical conditions you may have, such as kidney damage
Typically, your doctor will start you on a low dosage and adjust it over time to reach the dosage that’s right for you. They’ll ultimately prescribe the smallest dosage that provides the desired effect.
The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you.
Forms and strengths
Generic:
Dosage for high blood pressure
Adult dosage (ages 18 to 64 years)
- Typical starting dosage:
- Dosage increases:
Child dosage (ages 12 to 17 years)
- Typical starting dosage:
- Dosage increases:
Child dosage (ages 3 to 11 years)
- Typical dosage:
- Maximum daily dosage:
Child dosage (ages 6 months to 2 years)
- Typical dosage:
- Maximum daily dosage:
Child dosage (ages 0 to 6 months)
Senior dosage (ages 65 years and older)
There are no specific recommendations for senior dosing. Older adults may process drugs more slowly. A normal adult dosage may cause levels of this drug to be higher than normal in your body. If you’re a senior, you may need a lower dosage or a different dosing schedule.
Dosage for edema
Adult dosage (ages 18 to 64 years)
- Typical dosage:
- Intermittent therapy:
Child dosage (ages 12 to 17 years)
- Typical dosage:
- Intermittent therapy:
Child dosage (ages 3 to 11 years)
- Typical dosage:
- Maximum daily dosage:
Child dosage (ages 6 months to 2 years)
- Typical dosage:
- Maximum daily dosage:
Child dosage (ages 0 to 6 months)
Senior dosage (ages 65 years and older)
There are no specific recommendations for senior dosing. Older adults may process drugs more slowly. A normal adult dosage may cause levels of this drug to be higher than normal in your body. If you’re a senior, you may need a lower dosage or a different dosing schedule.