Isosorbide dinitrate

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.

Chemical properties

white to light yellow crystal powde

Originator

Isordil,Ives,US,1959

The Uses of Isosorbide dinitrate

Isosorbide dinitrate is also used in chronic cardiac insufficiency for preventing angina pectoris attacks. It is a long-lasting drug.

The Uses of Isosorbide dinitrate

Antianginal;Nitric oxide (NO) donor

The Uses of Isosorbide dinitrate

Coronary vasodilator

Background

A vasodilator used in the treatment of angina pectoris. Its actions are similar to nitroglycerin but with a slower onset of action.

Indications

For the prevention of angina pectoris due to coronary artery disease.

Definition

ChEBI: Isosorbide dinitrate is a nitrate ester and a glucitol derivative. It has a role as a vasodilator agent and a nitric oxide donor.

Manufacturing Process

An aqueous syrup of 1,4:3,6-dianhydro-D-glucitol is slowly added to a cooled mixture of HNO3 and H2SO4. After standing a few minutes the mixture is poured into cold water and the precipitated product is collected and recrystallized from ethanol.

brand name

Dilatrate (Schwarz Pharma); Isordil (Biovail); Isordil (Wyeth); Sorbitrate (AstraZeneca).

Therapeutic Function

Coronary vasodilator

General Description

A crystalline solid. May be toxic by ingestion. Used to make pharmaceuticals. Used as a heart drug.

Air & Water Reactions

Highly flammable. Slightly soluble in water.

Reactivity Profile

Nitroalkanes, such as Isosorbide dinitrate, range from slight to strong oxidizing agents. If mixed with reducing agents, including hydrides, sulfides and nitrides, they may begin a vigorous reaction that culminates in a detonation. Nitroalkanes are milder oxidizing agents, but still react violently with reducing agents at higher temperature and pressures. Nitroalkanes react with inorganic bases to form explosive salts. The presence of metal oxides increases the thermal sensitivity of nitroalkanes. Nitroalkanes with more than one nitro group are generally explosive. Nitroalkanes are insoluble in water. This heart drug is detonable when dry, but non-explosive with 30% of water.

Health Hazard

Fire may produce irritating and/or toxic gases. Contact may cause burns to skin and eyes. Contact with molten substance may cause severe burns to skin and eyes. Runoff from fire control may cause pollution.

Fire Hazard

Flammable/combustible material. May be ignited by friction, heat, sparks or flames. Some may burn rapidly with flare burning effect. Powders, dusts, shavings, borings, turnings or cuttings may explode or burn with explosive violence. Substance may be transported in a molten form at a temperature that may be above its flash point. May re-ignite after fire is extinguished.

Pharmacokinetics

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.

Clinical Use

Vasodilator:
Prophylaxis and treatment of angina
Left ventricular failure

Safety Profile

Moderately toxic by ingestion, intraperitoneal, intramuscular, and subcutaneous routes. Experimental reproductive effects. Mutation data reported. A flammable solid. When heated to decomposition it emits toxic fumes of NOx. A coronary vasodilator. See also NITRATES.

Synthesis

Isosorbiddinitrate, 1,4:3,6-dianhydrosorbate-2,5-dinitrate (19.1.4), is synthesized by intermolecular dehydration of D-sorbite into isosorbide (19.1.3) using paratoluenesulfonic acid and subsequent nitration of the two hydroxyl groups by nitric acid.

Veterinary Drugs and Treatments

Isosorbide mononitrate (ISMN) and dinitrate (ISDN) are organic nitrates potentially useful as preload reducing agents in treating heart failure in small animals, however, research and clinical experience demonstrating clinical efficacy are lacking in dogs or cats. Limited research indicates that dogs may require much higher dosages of isosorbide dinitrate to achieve therapeutic effects than do humans.
In humans, isosorbide nitrates are used for treating or preventing angina, treating esophageal spasm, and as an adjunctive treatment in CHF.

Metabolism

Hepatic