Chlorthalidone should be used with caution in severe renal disease. In patients with renal disease, chlorthalidone or related drugs may precipitate azotemia. Cumulative effects of the drug may develop in patients with impaired renal function. Chlorthalidone should be used with caution in patients with impaired hepatic function or progressive liver disease, because minor alterations of fluid and electrolyte balance may precipitate hepatic coma.
Sensitivity reactions may occur in patients with a history of allergy or bronchial asthma.
The possibility of exacerbation or activation of systemic lupus erythematosus has been reported with thiazide diuretics which are structurally related to chlorthalidone. However, systemic lupus erythematosus has not been reported following chlorthalidone administration.
There is currently no manufacturer warning information available for this drug.
CLORPRES® (clonidine hydrochloride USP/chlorthalidone USP) is indicated in the treatment of hypertension. This fixed combination drug is not indicated for initial therapy of hypertension. Hypertension requires therapy titrated to the individual patient. If the fixed combination represents the dosage so determined, its use may be more convenient in patient management. The treatment of hypertension is not static, but must be reevaluated as conditions in each patient warrant.
CLORPRES® is a combination of clonidine hydrochloride (a centrally acting antihypertensive agent) and chlorthalidone (a diuretic). CLORPRES® is available as tablets for oral administration in three dosage strengths: 0.1 mg/15 mg, 0.2 mg/15 mg and 0.3 mg/15 mg of clonidine hydrochloride/chlorthalidone, respectively.
The inactive ingredients are ammonium chloride, colloidal silicon dioxide, croscarmellose sodium (Type A), magnesium stearate, microcrystalline cellulose, sodium lauryl sulfate, D&C yellow #10.
Clonidine Hydrochloride
Clonidine hydrochloride is an imidazoline derivative and exists as a mesomeric compound. The chemical name is 2-[(2,6-dichlorophenyl)imino]imidazoline monohydrochloride. The following are the structural formula, molecular formula and molecular weight:
Clonidine hydrochloride is an odorless, bitter, white crystalline substance soluble in water and alcohol.
Chlorthalidone
Chlorthalidone is a monosulfamyl diuretic that differs chemically from thiazide diuretics in that a double ring system is incorporated in its structure. It is 2-chloro-5-(1-hydroxy-3-oxo-1-isoindolinyl) benzenesulfonamide with the following structural formula, molecular formula and molecular weight:
Chlorthalidone is practically insoluble in water, in ether and in chloroform; soluble in methanol; slightly soluble in alcohol.
