Chlorthalidone was approved by the FDA in 1960. It belongs to a class of medications known as diuretics. Chlorthalidone is used alone or in combination with other medications in the treatment of high blood pressure. It is also used as adjunctive therapy for fluid retention (edema) caused by congestive heart failure, renal disease, liver cirrhosis, estrogen therapy and corticosteroid therapy. This medication works by increasing the excretion of water from the body. Chlorthalidone has been found to cause potassium loss from the body as well as increase levels of uric acid. Chlorthalidone is a long-acting thiazide derivative with low toxicity.
Dosage and Form
Chlorthalidone comes in tablet form in 25mg and 50mg strengths.
When using chlorthalidone as therapy for hypertension, most patients should be initiated with a single daily dose of 25 mg. If the response is insufficient after a suitable trial, the dosage may be increased to a single daily dose of 50 mg. If additional control is required, the dosage of Chlorthalidone may be increased further to 100 mg once daily or a second antihypertensive drug may be added. Dosage above 100 mg daily usually does not increase effectiveness.
Before Taking Chlorthalidone
Before taking Chlorthalidone make sure your doctor or pharmacist knows:
if you are pregnant, trying for a baby or breast-feeding
if you suffer from liver or kidney problems
if you suffer from Addison's disease, diabetes, gout, porphyria (a blood disorder) or systemic lupus erythematosus (SLE)
if you suffer from prostate problems or have problems urinating (passing water)
if you have ever had an allergic reaction to this or any other medicine
if you are taking any other medicines, including those available to buy without a prescription, herbal and complementary medicines
if you have any other medical conditions
Side Effects
The following side effects are the most common side effects associated with chlorthalidone use. Talk to your doctor if any of these conditions persist or become bothersome while taking chlorthalidone:
Dizziness
Constipation
Headache
Lightheadedness
While the following side effects are less common, they may be severe. Seek medical attention right away if you experience any of these symptoms while taking chlorthalidone:
Severe allergic reaction
Drowsiness
Dry mouth
Impotence
Muscle pain or cramps
Nausea
Rapid or irregular heart beat
Restlessness
Unusual thirst
Unusual tiredness or weakness
Vomiting
Yellowing of the skin or eyes
Who Should Not Take Chlorthalidone?
Chlorthalidone should not be taken by anyone who:
has an allergy to any of the ingredients of this medication or to sulfa drugs
has low blood potassium that does not get better with supplementation