Disulfiram

INDICATIONS AND USAGE Disulfiram is an aid in the management of selected chronic alcohol patients who want to remain in a state of enforced sobriety so that supportive and psychotherapeutic treatment may be applied to best advantage. Disulfiram is not a cure for alcoholism. When used alone, without proper motivation and supportive therapy, it is unlikely that it will have any substantive effect on the drinking pattern of the chronic alcoholic.

DOSAGE AND ADMINISTRATION Disulfiram should never be administered until the patient has abstained from alcohol for at least 12 hours. Initial Dosage Schedule In the first phase of treatment, a maximum of 500 mg daily is given in a single dose for one to two weeks. Although usually taken in the morning, disulfiram may be taken on retiring by patients who experience a sedative effect. Alternatively, to minimize, or eliminate, the sedative effect, dosage may be adjusted downward. Maintenance Regimen The average maintenance dose is 250 mg daily (range, 125 to 500 mg), it should not exceed 500 mg daily. Note : Occasionally patients, while seemingly on adequate maintenance doses of disulfiram, report that they are able to drink alcoholic beverages with impunity and without any symptomatology. All appearances to the contrary, such patients must be presumed to be disposing of their tablets in some manner without actually taking them. Until such patients have been observed reliably taking their daily disulfiram tablets (preferably crushed and well mixed with liquid), it cannot be concluded that disulfiram is ineffective. Duration of Therapy The daily, uninterrupted administration of disulfiram must be continued until the patient is fully recovered socially and a basis for permanent self-control is established. Depending on the individual patient, maintenance therapy may be required for months or even years. Trial with Alcohol During early experience with disulfiram, it was thought advisable for each patient to have at least one supervised alcohol-drug reaction. More recently, the test reaction has been largely abandoned. Furthermore, such a test reaction should never be administered to a patient over 50 years of age. A clear, detailed and convincing description of the reaction is felt to be sufficient in most cases. However, where a test reaction is deemed necessary, the suggested procedure is as follows: After the first one to two weeks’ therapy with 500 mg daily, a drink of 15 mL (1/2 oz) of 100 proof whiskey, or equivalent, is taken slowly. This test dose of alcoholic beverage may be repeated once only, so that the total dose does not exceed 30 mL (1 oz) of whiskey. Once a reaction develops, no more alcohol should be consumed. Such tests should be carried out only when the patient is hospitalized, or comparable supervision and facilities, including oxygen, are available. Management of Disulfiram-Alcohol Reaction In severe reactions, whether caused by an excessive test dose or by the patient’s unsupervised ingestion of alcohol, supportive measures to restore blood pressure and treat shock should be instituted. Other recommendations include: oxygen, carbogen (95% oxygen and 5% carbon dioxide), vitamin C intravenously in massive doses (1 g) and ephedrine sulfate. Antihistamines have also been used intravenously. Potassium levels should be monitored, particularly in patients on digitalis, since hypokalemia has been reported.

ADVERSE REACTIONS (See CONTRAINDICATIONS , WARNINGS , and PRECAUTIONS .) OPTIC NEURITIS, PERIPHERAL NEURITIS, POLYNEURITIS, AND PERIPHERAL NEUROPATHY MAY OCCUR FOLLOWING ADMINISTRATION OF DISULFIRAM. Multiple cases of hepatitis, including both cholestatic and fulminant hepatitis, as well as hepatic failure resulting in transplantation or death, have been reported with administration of disulfiram. Occasional skin eruptions are, as a rule, readily controlled by concomitant administration of an antihistaminic drug. In a small number of patients, a transient mild drowsiness, fatigability, impotence, headache, acneform eruptions, allergic dermatitis, or a metallic or garlic-like aftertaste may be experienced during the first two weeks of therapy. These complaints usually disappear spontaneously with the continuation of therapy, or with reduced dosage. Psychotic reactions have been noted, attributable in most cases to high dosage, combined toxicity (with metronidazole or isoniazid), or to the unmasking of underlying psychoses in patients stressed by the withdrawal of alcohol.