Brands, Medical Use, Clinical Data
Drug Category
- Vasodilator Agents
- Nitrates and Nitrites
Dosage Forms
Brands / Synonyms
; Bidil; Cardio 10; Cardis; Carvanil; Carvasin; Cedocard; Claodical; Cornilat; Coronex; Corosorbide; Dianhydrosorbitol 2,5-dinitrate; Difutrat; Dilatrate; Dilatrate-SR; Dinitrosorbide; Emoper; Flindix; Harrical; IBD 20; ISD; ISDN; Ismotic; Iso-Bid; Isochron; Isoket; Isorbid; Isordil; Isordil Tembids; Isosorbide dinitrate(USAN); Isostat; Isotrate; Korodil; Lomilan; Maycor; Myorexon; Nitrosorbid; Nitrosorbide; Nitrosorbon; Nosim; Resoidan; Rifloc Retard; Rigedal; Sorbangil; Sorbide nitrate; Sorbide T.D.; Sorbide, dinitrate; Sorbidilat; Sorbidnitrate; Sorbislo; Sorbitrate; Sorbonit; Sorquad; Tinidil; Titradose; Vascardin; Vasodilat; Vasorbate; Xanyl
Indications
For the prevention of angina pectoris due to coronary artery disease.
Pharmacology
Isosorbide Dinitrate is a moderate to long acting oral organic nitrate used for the relief and prophylactic management of angina pectoris. It relaxes the vascular smooth muscle and consequent 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.
Mechanism of Action
Similar to other nitrites and organic nitrates, isosorbide dinitrate is converted to nitric oxide (NO), an active intermediate compound which activates the enzyme guanylate cyclase (atrial natriuretic peptide receptor A). This stimulates the synthesis of cyclic guanosine 3',5'-monophosphate (cGMP) which then activates a series of protein kinase-dependent phosphorylations in the smooth muscle cells, eventually resulting in the dephosphorylation of the myosin light chain of the smooth muscle fiber. The subsequent release of calcium ions results in the relaxation of the smooth muscle cells and vasodilation.
Absorption
Absorption of isosorbide dinitrate after oral dosing is nearly complete, but bioavailability is highly variable (10% to 90%), with extensive first-pass metabolism in the liver. The average bioavailability of isosorbide dinitrate is about 25%.
Toxicity
Symptoms of overdose include reduced cardiac output and hypotension.
Biotrnasformation / Drug Metabolism
Hepatic
Contraindications
Allergic reactions to organic nitrates are extremely rare, but they do occur. Isosorbide dinitrate is contraindicated in patients who are allergic to isosorbide dinitrate or any of its other ingredients.
Drug Interactions
DRUG INTERACTIONS
The vasodilating effects of isosorbide dinitrate may be additive with those of other vasodilators.
Alcohol, in particular, has been found to exhibit additive effects of this variety.
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