Key takeaways:
Hydrochlorothiazide (Microzide) is a medication used to treat high blood pressure and fluid buildup. The medication name is often abbreviated as HCTZ.
You should take HCTZ in the morning with food unless your healthcare provider tells you otherwise. If you miss a dose, take it as soon as you remember, but don’t take a double dose.
If you have side effects from taking HCTZ, such as low blood pressure, weakness, or rash, let your healthcare provider know.
Hydrochlorothiazide (Microzide) is a commonly prescribed medication in the U.S. In fact, as of 2019, it was the 11th most common prescription medication, with over 9 million people taking it. It’s often referred to as HCTZ, an abbreviation for the medication.
If you’re taking HCTZ, your healthcare provider likely prescribed it to help you treat high blood pressure or fluid buildup (edema). But, as with any medication, you may be wondering how to get the most out of your prescription. Well, we have some tips.
Let’s first discuss how HCTZ works: it’s a diuretic (“water pill”) that works in the kidneys. Like other diuretics, it helps remove extra fluid from the body by urination. HCTZ is FDA-approved to treat high blood pressure and edema (fluid buildup in body tissues).
HCTZ removes fluid by raising the amount of sodium in the urine. This causes fluid to move out of the bloodstream and into the urine. When used long-term for high blood pressure, it’s unclear exactly how HCTZ works. Experts believe it may help widen the blood vessels or change how the kidneys regulate blood pressure.
HCTZ is a specific type of water pill called a thiazide diuretic. Other thiazide and “thiazide-like” diuretics include:
Chlorothiazide (Diuril)
Metolazone (Zaroxolyn)
It's important to take HCTZ as prescribed by your healthcare provider. Here are a few tips on how to do that, and how to get the most out of the medication.
You can take HCTZ either in the morning or at night. But, your healthcare provider will likely tell you to take it in the morning so it doesn't interfere with your sleep. This is because HCTZ causes you to urinate more in the hours following your dose. It may be easier to manage this expected side effect during the day, rather than having to get up at night to use the bathroom.
If you're taking HCTZ more than once a day, you can split the doses up and take them at different times of day. But unless instructed by your provider, it’s best to avoid taking doses in the evening hours.
You can take HCTZ with food if you’d prefer. This can help lower the chance of getting an upset stomach. But, taking HCTZ without food won’t affect how the medication works.
It depends. For most other blood pressure medications, you don't need to separate your dose of HCTZ. In fact, many blood pressure medications are combination products, like lisinopril/hydrochlorothiazide (Zestoretic).
But there are a few medications that can interact with HCTZ. These medication doses may need to be separated. For example, cholestyramine (Prevalite) and colestipol (Colestid) can lower absorption of HCTZ. You should take HCTZ at least 1 hour before or 4 to 6 hours after cholestyramine or colestipol.
These aren’t the only possible interactions for HCTZ. Be sure to share a current medication list with your healthcare provider and pharmacist.
If you miss a dose of HCTZ, take it as soon as you remember. If it's almost time for your next dose, skip the missed dose and take your next dose at the regular time. Never take two doses of HCTZ at the same time. This could lead to worse side effects.
Most people tolerate HCTZ well. If you experience side effects from HCTZ, talk to your healthcare provider. They may be able to offer tips to help manage them.
There are many side effects that can occur when taking HCTZ. Some of the reported side effects that are usually mild include:
More frequent urination
Weakness
Low blood pressure
Constipation or diarrhea
Nausea or vomiting
Being more sensitive to the sun
Raised blood sugar
Higher levels of uric acid (can lead to gout attacks)
Serious side effects from HCTZ are rare, but may include:
Allergic reactions
Blurry vision or other vision changes
Severe body rashes, such as Stevens-Johnson Syndrome
Low potassium (hypokalemia) or low sodium (hyponatremia)
Some allergic reactions can be severe, such as anaphylaxis. Call 911 or seek immediate medical attention if you experience trouble breathing or swelling of the lips, tongue, or throat.
Changes to electrolyte levels, such as potassium or sodium, may not always cause symptoms. That’s why it’s important to go for any blood tests your healthcare provider recommends. These tests help your provider make sure your electrolyte levels are OK while taking HCTZ.
There are many ways to save on HCTZ, which is available as both a brand-name and generic medication.
Save with GoodRx. GoodRx can help you save about 60% off the average retail price of the generic version. Generic HCTZ’s price at certain pharmacies is about $5 with a free GoodRx discount.
Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for the PAN Foundation’s patient assistance program, which offers the medication free of cost.
Hydrochlorothiazide is a safe and effective medication for treating high blood pressure. It’s sometimes used to treat fluid buildup as well. Be sure to take it as prescribed by your healthcare provider and let them know if you experience any side effects.
Remember that when taking HCTZ it’s best to take it at the same time each day, usually in the morning. Taking HCTZ with food can lower the chance of having an upset stomach. If you have questions or concerns about how to take HCTZ, you should check with your healthcare provider or pharmacist.
HCTZ generally has a low cost. Making sure you have the generic version and using your insurance or a GoodRx discount can help you get the best price on your medication.
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