home > drugs a-z list > thalitone (chlorthalidone) drug center > thalitone (chlorthalidone) drug - clinical pharmacology

Recommended Topic Related To:

Thalitone

High blood pressure facts

  • High blood pressure (hypertension) is designated as either essential (primary) hypertension or secondary hypertension and is defined as a consistently elevated blood pressure exceeding 140/90 mm Hg.
  • High blood pressure is called "the silent killer" because it often causes no symptoms for many years, even decades, until it finally damages certain critical organs.
  • Poorly controlled high blood pressure ultimately can cause damage to blood vessels in the eye, thickening of the heart muscle and heart attacks, hardening of the arteries (arteriosclerosis), kidney failure, and strokes.
  • Most antihypertensive medications can be used alone or in combination. Some are used only in combination. Some are preferred over others in certain specific medical situations. And some are not to be used (contraindicated) in other situations.
  • Several classes of antihypertensive medications are available, including ACE i...

Thalitone

font size

CLINICAL PHARMACOLOGY

Chlorthalidone is a long-acting oral diuretic with antihypertensive activity. Its diuretic action commences a mean of 2.6 hours after dosing and continues for up to 72 hours.The drug produces diuresis with increased excretion of sodium and chloride.The diuretic effects of chlorthalidone and the benzothiadiazine (thiazide) diuretics appear to arise from similar mechanisms and the maximal effect of chlorthalidone and the thiazides appear to be similar. The site of the action appears to be the distal convoluted tubule of the nephron. The diuretic effects of chlorthalidone lead to decreased extracellular fluid volume, plasma volume, cardiac output, total exchangeable sodium, glomerular filtration rate, and renal plasma flow. Although the mechanism of action of chlorthalidone and related drugs is not wholly clear, sodium and water depletion appear to provide a basis for its antihypertensive effect. Like the thiazide diuretics, chlorthalidone produces dose-related reductions in serum potassium levels,elevations in serum uric acid and blood glucose, and it can lead to decreased sodium and chloride levels.

The mean plasma half-life of chlorthalidone is about 40 to 60 hours. It is eliminated primarily as unchanged drug in the urine.Non-renal routes of elimination have yet to be clarified. In the blood,approximately 75% of the drug is bound to plasma proteins.

Thalitone® (chlorthalidone USP) has been formulated with PVP (povidone polyvinylpyrrolidone), a bioavailability enhancer that provides 104% to 116% bioavailability relative to an oral solution of chlorthalidone. Thalitone® (chlorthalidone) cannot be substituted for other formulations of chlorthalidone and likewise, other formulations of chlorthalidone cannot be substituted for Thalitone® (chlorthalidone) .

Last reviewed on RxList: 7/16/2008
This monograph has been modified to include the generic and brand name in many instances.

Report Problems to the Food and Drug Administration

 

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.


Women's Health

Find out what women really need.