Drug Groups

approved

Description

An indandione that has been used as an anticoagulant. Phenindione has actions similar to warfarin, but it is now rarely employed because of its higher incidence of severe adverse effects. (From Martindale, The Extra Pharmacopoeia, 30th ed, p234)

Indication

For the treatment of pulmonary embolism, cardiomyopathy, atrial fibrillation and flutter, cerebral embolism, mural thrombosis, and thrombophili. Also used for anticoagulant prophylaxis.

Pharmacology

Phenindione thins the blood by antagonizing vitamin K which is required for the production of clotting factors in the liver. Anticoagulants such as Phenindione have no direct effect on an established thrombus, nor do they reverse ischemic tissue damage (damage caused by an inadequate blood supply to an organ or part of the body). However, once a thrombus has occurred, the goal of anticoagulant treatment is to prevent further extension of the formed clot and prevent secondary thromboembolic complications which may result in serious and possibly fatal sequelae. Phenindione has actions similar to warfarin, but it is now rarely employed because of its higer incidence of severe adverse effects.

Toxicity

Oral, mouse: LD50 = 175 mg/kg; Oral, rat: LD50 = 163 mg/kg.

Affected Organisms

Biotransformation

Hepatic.

Absorption

Absorbed slowly from the gastrointestinal tract.

Half Life

5-10 hours

Protein Binding

88%

References

External Links