A brief note on Disulfiram
Disulfiram is a drug used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (drinking alcohol). Disulfiram works by inhibiting the enzyme acetaldehyde dehydrogenase, causing many of the effects of a hangover to be felt immediately following alcohol consumption. Disulfiram plus alcohol, even small amounts, produces flushing, throbbing in the head and neck, a throbbing headache, respiratory difficulty, nausea, copious vomiting, sweating, thirst, chest pain, palpitation, dyspnea, hyperventilation, fast heart rate, low blood pressure, fainting, marked uneasiness, weakness, vertigo, blurred vision, and confusion. In severe reactions there may be respiratory depression, cardiovascular collapse, abnormal heart rhythms, heart attack, acute congestive heart failure, unconsciousness, convulsions, and death. In the body, alcohol is converted to acetaldehyde, which is then broken down by acetaldehyde dehydrogenase. When the dehydrogenase enzyme is inhibited, acetaldehyde builds up, causing unpleasant side effects. Disulfiram should be used in conjunction with counselling and support. Alcohol dependence Disulfiram is used as a second line treatment, behind acamprosate and naltrexone, for alcohol dependence. Under normal metabolism, alcohol is broken down in the liver by the enzyme alcohol dehydrogenase to acetaldehyde, which is then converted by the enzyme acetaldehyde dehydrogenase to a harmless acetic acid derivative (acetyl coenzyme A). Disulfiram blocks this reaction at the intermediate stage by blocking acetaldehyde dehydrogenase. After alcohol intake under the influence of disulfiram, the concentration of acetaldehyde in the blood may be five to 10 times higher than that found during metabolism of the same amount of alcohol alone. As acetaldehyde is one of the major causes of the symptoms of a "hangover", this produces immediate and severe negative reaction to alcohol intake. About 5 to 10 minutes after alcohol intake, the patient may experience the effects of a severe hangover for a period of 30 minutes up to several hours. Symptoms include flushing of the skin, accelerated heart rate, shortness of breath, nausea, vomiting, throbbing headache, visual disturbance, mental confusion, postural syncope, and circulatory collapse. Disulfiram should not be taken if alcohol has been consumed in the last 12 hours. There is no tolerance to disulfiram: the longer it is taken, the stronger its effects. As disulfiram is absorbed slowly through the digestive tract and eliminated slowly by the body, the effects may last for up to two weeks after the initial intake; consequently, medical ethics dictate that patients must be fully informed about the disulfiram-alcohol reaction. Disulfiram does not reduce alcohol cravings, so a major problem associated with this drug is extremely poor compliance. Methods to improve compliance include subdermal implants, which release the drug continuously over a period of up to 12 weeks, and supervised administration practices, for example, having the drug regularly administered by one's spouse. Although disulfiram remained the most common pharmaceutical treatment of alcohol abuse until the end of the 20th century, today it is often replaced or accompanied with newer drugs, primarily the combination of naltrexone and acamprosate, which directly attempt to address physiological processes in the brain associated with alcohol abuse. Submit manuscript at www.longdom.org/submissions/drug-metabolism-toxicology.html or send as an e-mail attachment to the Editorial Office at drugmetabol@eclinjournals.com Regards Lisa D Managing editor Journal of Drug Metabolism & Toxicology