Moduretic - Hydrochlorothiazide

The use of fixed combination of a thiazide and a potassium-sparing drug, often Moduretic (hydrochlorothiazide 50 mg with amiloride 5 mg), has been consistently implicated in diuretic-induced hyponatremia. Treatment with chlorpropamide (200-800 mg/day) along with Moduretic has precipitated hyponatremia in several cases (96). Simultaneous use of Moduretic with trimethoprim has also been reported to increase the risk (97). The mechanism appears to be impairment of the clearance of free water, resulting in dilutional hyponatremia. Whether... 

Amiloride exerts an inhibitory action on sodium channels under the influence of aldosterone in the distal tubule. Its action is therefore complementary to that of the thiazides and, used with them, it augments sodium loss and but limits potassium loss. One such combination, co-amilozide, (Moduretic) (amiloride 2.5-5 mg plus hydrochlorothiazide 25-50 mg), is used for hypertension or oedema. The maximum effect of amiloride occurs about 6 h after an oral dose with a duration of action >24h 21 h). The oral dose is 5-20 mg daily. 

Sweden s National Adverse Reaction Monitoring System called the attention of physicians to a case in which a 73-year-old woman developed anaphylactic shock after taking only a single tablet of Moduretic (7). The National System had received three other reports on anaphylactic reactions to this combination, and by 1988 the WHO center in Uppsala had received eight others from other countries. Except for mild skin reactions, hypersensitivity reactions to hydrochlorothiazide alone are highly unusual and not of this type. 

Indometacin reduces the effect of diuretics (69). Combination of indometacin with Moduretic (co-amilo-zide amiloride + hydrochlorothiazide) results in hyperkalemia (70). 

Amiloride/Hydrochtorothiazide, USP (Moduretic, Generic) Oral 5 mg amiloride hydrochloride/50 mg hydrochlorothiazide... 

Note Aldactazide is spironolactone and hydrochlorothiazide Aldoril is methyldopa and hydrochlorothiazide Avalide is irbesartan and hydrochlorothiazide Capozide is captopril and hydrochlorothiazide Dyazide is triamterene and hydrochlorothiazide Maxzide is triamterene and hydrochlorothiazide Moduretic is amiloride and hydrochlorothiazide Prinizide is lisinopril and hydrochlorothiazide... 

Potassium-sparing diuretics include amiloride HCl (Midamor) spironolactone (Aldactone), and triamterene (Dyrenium). Combination diuretics include amiloride HCl and hydrochlorothiazide (Moduretic) spironolactone and hydrochlorothiazide (Aldactazide), and triamterene and hydrochlorothiazide (Dyazide, Maxzide). 

Moduret (Amiloride/Hydrochlorothiazide). Bristol-Myers Squibb Pharmaceuticals Ltd. UK Summary of product characteristics, September 2006. 

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