Hydrochlorothiazide
MicrozidePubChem CID 3639 · 3D model
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Helps the kidneys flush out extra salt and water, which lowers blood pressure.
How it works
This medicine blocks a specific salt-transport channel in the kidney's filtering tubes, so less salt and chloride get reabsorbed into the blood and more gets flushed out in urine, taking water with it. Losing that extra fluid lowers the total volume of blood the heart has to pump, which brings blood pressure down at first. Over time, blood volume evens back out, but blood pressure stays lower because blood vessels relax more easily. Because more salt is passing through the kidneys, the body also loses more potassium than usual, which is why blood levels sometimes need to be monitored.
What it’s used for
Approved to treat high blood pressure, either on its own or alongside other blood pressure medicines. Other versions of this drug are also approved to help reduce fluid buildup and swelling caused by heart failure, liver disease, certain hormone medications, or kidney problems.
- Mechanism
- Thiazide diuretic (Na+/Cl- cotransporter inhibitor)
- Drug class
- Small molecule
- Therapeutic area
- Cardiovascular