Antabuse is not a magic pill to make alcohol less intoxicating – it will not safely get you through withdrawal either. Its job is much more simple: the pill makes drinking when taking it likely to produce very unpleasant side-effects.
The generic name for the drug is disulfiram. Doctors have been prescribing it for alcohol dependence since the 1950s usually to people who have opted to stop and want something to make an impulsive return to drinking more difficult.
For the right person, this can be extremely useful. The important word is right. For Antabuse to be useful, it needs to be taken voluntarily and paired with real support, not handed to someone still drinking or slipped into their food.
Why alcohol and Antabuse do not mix
When we drink, our bodies first turn alcohol into a substance called acetaldehyde. It is toxic, but our bodies usually break it down pretty quickly using an enzyme in the liver.
Antabuse blocks the action of that enzyme.
Drink alcohol after taking the medicine and acetaldehyde can build up in your system within minutes. The complexion becomes suddenly hot and red followed by a pounding headache, nausea, sweating and a racing heart. Some people vomit or find they cannot catch their breath.
It is easy to imagine why that would put someone off another drink.
The reaction can also go much further than misery-inducing. Blood pressure can drop very sharply and chest pain, fainting, an irregular heart rhythm or even a seizure can occur in a severe case. A large amount of alcohol is more likely to cause trouble, but there is no reliable “safe” amount to see whether the tablet you took yesterday has worn off.
So, how does Antabuse last in your system?
Longer than you might think.
The body breaks down disulfiram gradually, but the practical effects last up and beyond point when most of the original medication has been removed from the bloodstream. It has affected some of the enzymes the body uses to break down alcohol, and your body will need to manufacture some new ones.
Because of this, alcohol could still trigger a reaction for up to 14 days after your final tablet.
Not everyone will react strongly to medication for the full two weeks. The problem is you cannot feel the enzymes recovering, and there is no reliable test you can do at home. Skipping your pills for a day or two will not give you a safe window to have a drink.
Alcohol should also be avoided before starting treatment. Official prescribing information says at least 12 hours should have passed since your last drink before the first tablet, though a doctor may suggest waiting longer depending on your circumstances.
Anyone who is drinking heavily every day should consult a doctor before suddenly stopping – alcohol withdrawal can cause hallucinations, seizures and delirium, and Antabuse will not stop any of that.
Check more than your drinks cabinet
A patient once told me how they had done everything right – no wine, beer or spirits – but felt suddenly flushed and ill after taking a generous dose of nighttime cough medicine. The syrup contained alcohol.
Cough and cold remedies are only one example – alcohol can also be found in mouthwashes, cooking extracts, sauces, desserts and some low-alcohol drinks. Aftershave, perfume, hand sanitizer and rubbing alcohol can occasionally cause trouble if a large amount is used or the fumes are inhaled in a confined space.
There is no need to have alarm bells go off every time you see a label in the bathroom, but there is a need to read the small print.
Be especially careful of products that say “non-alcoholic.” This does not always mean absolutely zero, and when in doubt, a pharmacist can check what is in the bottle and may suggest an alternative.
What taking Antabuse is actually like
Some people report feeling little from the actual tablet, while others feel tired, get headaches or complain about a metallic or garlicky taste. Mild stomach upset and skin rashes are also possible. Drowsiness tends to be worse at the start and then settle.
Issues with the liver are uncommon, but serious enough to not be ignored. A blood test at the beginning and during treatment may be recommended. Dark urine, yellow eyes, persistent vomiting, unusual tiredness or loss of appetite should prompt a call to a healthcare provider.
Numbness, tingling, weakness, confusion or changes in vision also need to be looked at.
A full review of medications is important before starting the first tablet. Disulfiram should not be taken with metronidazole and can interact with certain drugs including warfarin and phenytoin. Heart disease, liver problems, seizures, diabetes, pregnancy or a history of psychosis should all be raised with the prescriber.
It is a barrier, not the entire treatment
Antabuse does not magic away your desire to drink. You can still finish work feeling stressed, pass the usual bar and feel that old pull. What the tablet does is put a consequence in your path.
That is why the medicine often works better when someone else is in the picture – a partner to watch your morning dose, a counselor to know when the weekends get tricky, or a support group to discuss relapses without pretending they didn’t happen.
Other medications for alcohol dependence take a slightly different route. Naltrexone can reduce the rewarding effects of alcohol and potentially help with heavy drinking, while acamprosate is used to aid abstinence after drinking has stopped. Neither is necessarily better – they simply suit different people.
When Antabuse is chosen, the plan should stretch to more than the prescription – who will be monitoring your progress, what happens if you miss a dose, how will cravings be managed and who do you call if you do relapse.
The fact to remember is simple, but can be easily buried in all the warnings. Stopping the tablets does not immediately switch off their effects. For the next 14 days, treat alcohol like you are still taking the medication – because your body may decide so.
