Even though chlorthalidone and hydrochlorothiazide are structurally similar compounds, they are quite different.
They differ in their dosing regimen, potency (strength), duration of action, and side effects.
There is also a huge difference in the prescription ratio of these drugs.
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HCTZ is the preferred choice in most cases.
Thiazide diuretics have been commonly used as first-line agents for the treatment of hypertension.
They have proven effective at lowering blood pressure, being safe, and being low cost.
Chlorthalidone and HCTZ belong to the thiazide class ofdiureticsclass, also sometimes referred to as “water pills.”
They work by helping the kidneys remove salt and water reabsorption from the body and increase urination.
These drugs are both proven effective at treating high blood pressure.
However, other studies suggest that chlorthalidone is stronger and has a longer duration of action.
But it has a higher risk of side effects, such aselectrolyte imbalance.
Usually, HCTZ is the preferred choice of healthcare professionals.
HCTZ is prescribed more often than chlorthalidone.
However, these drugs are equally effective in studies on their effects on heart disease risk and mortality.
Another analysis showed that chlorthalidone was better than hydrochlorothiazide at controlling blood pressure.
Can You Use Chlorthalidone and HCTZ Together?
Usually, your healthcare provider will prescribe either chlorthalidone or HCTZ.
These drugs have the same action mechanism, so taking them together can lead to side effects.
Dosage
Chlorthalidone and HCTZ are available in tablet formulations that can be taken orally.
Chlorthalidone is available in 25 milligram (mg) or 50 mg strength tablets.
The drug, however, lasts about six to 12 hours in the body.
On the other hand, chlorthalidone lasts longer in the body than other diuretics, including HCTZ.
It starts working within two to three hours, and its effects last up to 72 hours.
Risk of Electrolyte Imbalances
Diuretics can cause anelectrolyte imbalance.
The risk of hyponatremia is usually higher with chlorthalidone when compared with hydrochlorothiazide.
If feeling dehydrated, you could also take an oral rehydration system (ORS).
ORS is a punch in of fluid used to treat or prevent dehydration.
It is available over the counter or by prescription.
In addition to water, ORS contains specific amounts of glucose and electrolytes, potassium, and sodium.
These components maximize fluid absorption in the gastrointestinal tract.
In case of severe symptoms, seek immediate medical help.
Your healthcare provider may prescribe more than one medicine or a combination pill containing two different drugs.
Chlorthalidone and HCTZ are individually combined with other blood pressure drugs in combination medications.
They are also available in combination with other blood pressure drugs.
These drugs work similarly to excrete excess water and salt from the body into the urine.
However, they differ in their doses, duration of action and side effects.
Although they are nearly equally effective in treating the indications, some studies prefer one drug over the other.
Your healthcare provider will determine the best treatment for you, considering the potential benefits and side effects.
2023;15(4):e38184.
DailyMed.Label: Chlorthalidone tablets.
2014;127(8):763-y71.
