ISOSORBIDE- isosorbide mononitrate tablet, film coated, extended release
West-Ward Pharmaceuticals Corp
ISOSORBIDE MONONITRATE
EXTENDED-RELEASE
TABLETS , USP
Rev. 05/16
Rx Only
DESCRIPTION
Isosorbide mononitrate (ISMN), an organic nitrate and the major biologically active metabolite of isosorbide dinitrate (ISDN), is a vasodilator with effects on both arteries and veins.
Isosorbide Mononitrate Extended-Release Tablets, USP, for oral administration, contain 30 mg or 60 mg of isosorbide mononitrate in an extended-release formulation. In addition, each tablet contains the following inactive ingredients: ammonium phosphate dibasic, anhydrous lactose, carnauba wax, colloidal silicon dioxide, hypromellose, magnesium stearate, and synthetic paraffin wax. Film coating and polishing solution contains: hypromellose, polyethylene glycol, red iron oxide (30 mg tablet only), titanium dioxide, and yellow iron oxide (60 mg tablet only).
The chemical name for ISMN is 1,4:3,6-dianhydro-,D-glucitol 5-nitrate; the compound has the following structural formula:
The following structural formula of ISMN is a white, crystalline, odorless compound which is stable in air and in solution, has a melting point of about 90�C, and an optical rotation of +144� (2% in water, 20�C).
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ISMN is a white, crystalline, odorless compound which is stable in air and in solution, has a melting point of about 90�C, and an optical rotation of +144� (2% in water, 20�C).
Isosorbide mononitrate is freely soluble in water, ethanol, methanol, chloroform, ethyl acetate, and dichloromethane. This drug product meets the USP Dissolution Test No. 3.
CLINICAL PHARMACOLOGY
Mechanism of Action :
The Isosorbide Mononitrate Extended-Release Tablets, USP product is an oral extended-release formulation of ISMN, the major active metabolite of isosorbide dinitrate; most of the clinical activity of the dinitrate is attributable to the mononitrate.
The principal pharmacological action of ISMN and all organic nitrates in general is relaxation of vascular smooth muscle, producing dilatation of peripheral arteries and veins, especially the latter. Dilatation of the veins promotes peripheral pooling of blood and decreases venous return to the heart, thereby reducing left ventricular end-diastolic pressure and pulmonary capillary wedge pressure (preload). Arteriolar relaxation reduces systemic vascular resistance, systolic arterial pressure and mean arterial pressure (afterload). Dilatation of the coronary arteries also occurs. The relative importance of preload reduction, afterload reduction, and coronary dilatation remains undefined.
