Hydrochlorothiazide oral tablet side effects: A detailed guide

Key takeaways

• Hydrochlorothiazide is a diuretic medication used to treat high blood pressure and fluid retention, and it can cause both mild and serious side effects.
• Common side effects include dizziness, headache, and frequent urination, while serious side effects can include electrolyte imbalances and allergic reactions, some of which require immediate medical attention.
• It is important to discuss any existing health conditions and medications with your doctor before taking hydrochlorothiazide, as it can interact with alcohol and may not be safe during pregnancy or breastfeeding.

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Overview

This article describes the possible side effects of hydrochlorothiazide oral tablets. You’ll also find information on cost savings and coupon options for hydrochlorothiazide.

Hydrochlorothiazide oral tablet is a generic medication. It isn’t available in a brand-name version. Hydrochlorothiazide also comes in an oral capsule, which is available as the brand name Microzide, but this form isn’t described in this article. To learn more about this form, talk with your doctor.

You can explore this overview article to learn more about hydrochlorothiazide oral tablet, including the drug’s uses, dosage, and more.

More common side effects of hydrochlorothiazide

Hydrochlorothiazide oral tablet may cause mild or serious side effects. Here are some of the more common side effects of this medication.

Commonly reported side effects of hydrochlorothiazide oral tablet include:

• dizziness
• headache
• weakness
• nausea and vomiting
• frequent urination

Mild side effects of hydrochlorothiazide

Hydrochlorothiazide may cause certain mild side effects. Most often, mild side effects are temporary and can be easily managed. Tell your doctor or pharmacist if you have side effects that don’t go away or become bothersome.

Mild side effects of hydrochlorothiazide oral tablet that occurred in studies include:

• appetite loss
• abdominal cramps
• constipation
• diarrhea
• dizziness
• headache
• infection or inflammation in the salivary glands
• mild low blood pressure
• muscle spasm
• frequent urination
• nausea
• restlessness
• sun sensitivity
• temporary blurry vision
• upset stomach
• weakness
• vertigo
• vomiting
• hair loss*
• mild allergic reaction*

* To learn more about this side effect, see the “Side effects of hydrochlorothiazide in detail” section in the following section.

Hydrochlorothiazide oral tablet may cause more mild side effects than those listed above. For details, see the drug’s prescribing information.

Serious side effects of hydrochlorothiazide

Hydrochlorothiazide may cause certain serious side effects. If you have any serious side effects from hydrochlorothiazide oral tablet, call your doctor right away.

If you think you’re having a medical emergency or your side effects feel life threatening, take immediate action. Call 911 or a local emergency number, or go to the nearest emergency room.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while taking hydrochlorothiazide and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

Serious side effects of hydrochlorothiazide oral tablet that occurred in studies include:

• blood cell problems, including aplastic anemia or thrombocytopenia
• cholestasis (reduced or blocked bile flow from your liver)
• erectile dysfunction
• eye-related side effects, including vision that is tinted yellow or acute angle-closure glaucoma
• high blood sugar or glucose in urine, which can lead to type 2 diabetes over time
• orthostatic hypotension (low blood pressure when standing or sitting up, which may lead to falls or fainting)
• pancreatitis (inflammation in the pancreas)
• electrolyte problems, including low blood potassium levels*
• high uric acid level and gout*
• severe allergic reaction*

* To learn more about this side effect, see the “Side effects of hydrochlorothiazide in detail” section as follows.

Common questions about side effects of hydrochlorothiazide

Here are answers to some common questions about side effects of hydrochlorothiazide oral tablet. If you have other questions, talk with your doctor or pharmacist.

Do the different strengths of hydrochlorothiazide, such as 12.5 mg or 25 mg, cause different side effects?

Different strengths of hydrochlorothiazide may cause different side effects. For example, you may be at higher risk of side effects like low potassium and high blood sugar when taking higher doses of the drug.

Your risk for any side effects generally increases if you take a higher dose of hydrochlorothiazide compared to a lower dose. This is the case for most drugs. Your doctor or pharmacist can answer questions about how your dose impacts your risk for side effects.

What are the side effects of stopping hydrochlorothiazide?

Stopping hydrochlorothiazide isn’t known to cause side effects. Withdrawal symptoms weren’t reported in the drug’s studies. (Withdrawal symptoms are side effects that can occur when you stop taking a drug that your body has become dependent on.)

That said, do not stop taking hydrochlorothiazide without your doctor’s recommendation. If you stop treatment, the symptoms of the condition hydrochlorothiazide is being used to treat could come back. For example, fluid retention symptoms may return or worsen if you stop taking hydrochlorothiazide.

If you’d like to stop taking hydrochlorothiazide, your doctor can suggest other treatments for your condition that may be a better option for you.

Is weight gain a possible side effect of hydrochlorothiazide?

No, weight gain isn’t a side effect that’s expected with hydrochlorothiazide. This side effect wasn’t reported in the drug’s studies.

If you’re taking hydrochlorothiazide to treat fluid retention related to heart failure and have unexplained weight gain, you should contact your doctor right away. This isn’t a side effect hydrochlorothiazide is known to cause, and it may be a sign that your heart failure is worsening.

Does hydrochlorothiazide cause long-term side effects?

Yes, it’s possible, although rare.

Long-term side effects are those that start either:

• during treatment and continue for a long time, possibly after stopping treatment, or
• after you’ve taken the drug for a long time or after ending treatment

Long-term side effects reported with hydrochlorothiazide include:

• high blood sugar levels or glucose in urine, which may lead to diabetes
• high uric acid level, which may lead to gout*
• orthostatic hypotension (low blood pressure when standing or sitting up, which may lead to falls or fainting), which can occur at any time while taking hydrochlorothiazide but should go away if you stop treatment
• electrolyte problems, including low blood potassium levels*

Talk with your pharmacist or doctor if you have additional questions about hydrochlorothiazide and your risk for long-term side effects.

* To learn more about this side effect, see the following “Side effects of hydrochlorothiazide in detail” section.

Side effects of hydrochlorothiazide in detail

Here you’ll find details on some of the side effects of hydrochlorothiazide oral tablet.

Electrolyte problems

Hydrochlorothiazide is known to cause electrolyte problems, including low potassium, as a side effect.

Electrolyte problems hydrochlorothiazide may cause include:

• hypokalemia (low blood potassium level)
• hyponatremia (low blood sodium level)
• low blood chloride level, which can, in rare cases, lead to a serious condition called hypochloremic alkalosis
• hypomagnesemia (low blood magnesium level)
• hypercalcemia (high blood calcium level)

Symptoms of electrolyte problems caused by hydrochlorothiazide include:

• dry mouth
• increased thirst
• feeling weak or very tired
• restlessness
• nausea and vomiting
• urinating less than usual
• muscle pain, cramps, or weakness
• seizure

Ways to manage

If you think you’re having symptoms of an electrolyte problem while taking hydrochlorothiazide, immediately talk with a doctor. They’ll likely want to see you in person to further evaluate your symptoms.

How your doctor treats electrolyte problems caused by hydrochlorothiazide will depend on which electrolyte is affected and the severity of your symptoms.

For example, a low blood chloride level often won’t cause symptoms or need treatment except in very rare, serious cases.

On the other hand, low blood potassium is usually treated, even if it’s mild. For hypokalemia, your doctor may prescribe a potassium supplement or a potassium-sparing diuretic, such as spironolactone (Aldactone).

Hair loss

Hair loss is a rare but possible side effect reported in hydrochlorothiazide’s studies.

Symptoms of hair loss can include thinning hair. With hydrochlorothiazide, you’re not likely to have your hair fall out in clumps, although it may occur.

Ways to manage

Let your doctor know if you notice hair loss while taking hydrochlorothiazide. In most cases, this side effect should go away once you stop treatment with the drug.

Always check with your doctor before stopping a medication. If your doctor thinks stopping hydrochlorothiazide could help reverse hair loss, they can also recommend another medication to treat your condition that may be safer for you.

High uric acid level and gout

Treatment with hydrochlorothiazide may result in a high uric acid level (uricemia). This side effect was reported in the drug’s studies. This may lead to gout. Gout caused by this side effect of hydrochlorothiazide may require long-term treatment.

Having a high uric acid level doesn’t always cause symptoms. But some symptoms you may experience, especially if this develops into gout, can include:

• intense pain and swelling in the affected joint, usually your big toe
• warmth in the affected joint
• joint damage, if left untreated over time

This pain can occur suddenly, which is known as a gout attack.

Ways to manage

Talk with your doctor if you think you have symptoms of high uric acid or gout while taking hydrochlorothiazide. Your doctor may:

• temporarily or permanently stop your hydrochlorothiazide treatment, which should cause uric acid levels to lower back to usual
• lower your hydrochlorothiazide dose, which may cause uric acid levels to return to as usual
• prescribe a treatment for gout and have you continue taking hydrochlorothiazide at either the same or a lower dose

Allergic reaction

For some people, hydrochlorothiazide oral tablet can cause an allergic reaction. These reactions are reportedly rare, but may still happen.

Symptoms can be mild or serious, and they may include:

• itchiness
• skin rash
• swelling under the skin, usually affecting eyelids, lips, hands, or feet
• swelling of the mouth, tongue, or throat, which can make it hard to breathe
• flushing (temporary warmth, redness, or deepening of skin color)

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know if you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to hydrochlorothiazide oral tablet, your doctor may recommend taking a different medication instead.

Warnings for hydrochlorothiazide

Here are some factors you may want to discuss with your doctor before taking hydrochlorothiazide oral tablet.

Warnings

It may not be safe for you to take hydrochlorothiazide oral tablet if you have specific health conditions. These are sometimes called drug-condition interactions. Other things may also affect whether hydrochlorothiazide oral tablet is a safe treatment option for you.

Before taking hydrochlorothiazide oral tablet, tell your doctor about your health and medications you take. Things to consider include those in the following list.

• diabetes
• closed-angle glaucoma
• gout
• kidney problems, such as chronic kidney disease
• liver problems, such as alcoholic liver disease
• lupus
• past allergic reaction to hydrochlorothiazide or sulfonamide (“sulfa”) drugs

Hydrochlorothiazide and pregnancy

It’s not known whether hydrochlorothiazide is safe to take while pregnant. There isn’t enough data regarding the drug’s use in pregnant people to know whether the drug is safe or effective to take while pregnant.

If you’re planning a pregnancy or can become pregnant, talk with your doctor before taking this medication.

Hydrochlorothiazide and breastfeeding

Hydrochlorothiazide passes into breast milk, but there are no reports of it causing harm to breastfed babies. However, the decision to take it while breastfeeding should balance the mother’s needs with any possible risks to the baby.

Talk with your doctor to learn more about whether it’s safe for you to breastfeed your child based on the medications you may take.

Hydrochlorothiazide and alcohol

Hydrochlorothiazide oral tablet is known to interact with alcohol.

Drinking alcohol while taking hydrochlorothiazide raises your risk of low blood pressure when standing or sitting up. This side effect can result in falls or fainting, which can lead to severe injury.

If you drink alcohol, talk with your doctor about whether it’s safe to consume it during your treatment with hydrochlorothiazide oral tablet.

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.