Alcohol withdrawal: what happens in your body

Alcohol withdrawal usually begins 6 to 24 hours after the last drink, peaks between 24 and 72 hours, and is largely over after 5 to 7 days for most people. For heavy daily drinkers the process can be dangerous: delirium tremens typically begins 48 to 96 hours after stopping (PMID 25427113).

That makes alcohol the odd one out. It is the only substance on this list you can buy legally in any supermarket, and one of the few where stopping suddenly can end in an emergency department.

We think too few people know that. Anyone who wants to cut down gets applause, and rarely the question of how much was going in daily.

What happens in your body when you stop drinking?

Alcohol suppresses your nervous system. With prolonged use your body compensates by tuning that system to be more excitable. Remove the alcohol and that raised excitability is what remains, so the picture swings the other way: tremor, sweating, palpitations, nausea, agitation and insomnia (PMID 27586815).

That is not weakness and not a matter of willpower. It is a physiological correction that needs time.

For most moderate drinkers it stops at a few restless nights. For people who drink heavily every day, the picture can overshoot into confusion, hallucinations and seizures.

How long does alcohol withdrawal last?

The physical phase lasts five to seven days for most people, with the heaviest symptoms in the first three days. Sleep problems, irritability and mood swings often continue for weeks longer. That second phase is called post-acute withdrawal and moves in waves.

Alongside that symptom line runs a second line nobody shows you: what your blood and hair are doing over the same period.

That right-hand column is exactly what is missing from the rehab clinic pages. They describe how you feel, and stop there.

CDT and EtG were developed to assess alcohol use over a longer period and are used that way in forensic and clinical settings (PMID 29807559). What gamma-GT does and does not tell you is covered in gamma-GT too high.

When is alcohol withdrawal dangerous?

With daily heavy use, and in people who have previously had a seizure or delirium. Delirium tremens usually begins 48 to 96 hours after the last drink and brings confusion, hallucinations, fever and unstable blood pressure (PMID 25427113). Untreated, mortality is considerable.

There is another factor that rarely gets mentioned. Repeated withdrawal episodes can worsen the picture on a later attempt, including a higher seizure risk. That is called the kindling effect (PMID 27586815).

So someone who has already stopped and relapsed five times does not start a sixth attempt from zero.

In practice that means one thing: if you drink daily, discuss stopping with your GP first. They can assess the risk and supervise where needed. For confusion, hallucinations, heavy tremor or a seizure, call the out-of-hours service immediately, and 112 for a seizure.

We give no tapering schedule and no medication advice here. That belongs with a doctor who knows your situation.

Can you see whether your body is recovering?

Partly. Gamma-GT and CDT respond to stopping, but on a different timescale from your symptoms. Gamma-GT falls in many people over the weeks after stopping, and CDT usually normalises within a few weeks. Neither is a gauge of how you feel.

Take two people who stop on the same day, after 10 years of daily drinking. After three weeks one sleeps normally again and the other does not. Their CDT values at that moment can be near identical.

Body and head do not move in step.

What a dated series of values does do is record a pattern. In research on relapse in alcohol dependence, hair EtG and serum CDT were used side by side for exactly that (PMID 26851349). If you want that recorded for yourself, you can have an alcohol CDT test done without a referral, and only you see the result.

More on what CDT, EtG and a blood test each show is in proving alcohol use. What else changes in your blood after stopping is covered in quitting alcohol.

What can you do today?

Write down the date and time of your last drink. That sounds trivial, and it is the only information that makes every timeline above and every later result interpretable. Without that date, a CDT value or an EtG result is a number without context.

If you drink daily, make a GP appointment before you stop. RIVM tracks the Dutch figures on alcohol use, and Thuisarts.nl describes per situation when supervision is needed.

What keeps striking me about this subject: alcohol is the only substance here where stopping can be medically riskier than that week of drinking. I think that is far too rarely the first line on a page about cutting down.

How alcohol compares with other substances in withdrawal is set out in withdrawal symptoms by substance. To make abstinence over a longer period demonstrable, read abstinence and how to prove it objectively. The other life-threatening withdrawal is covered in GHB addiction.

Every blood test result at Zuivertest includes a professional assessment by a BIG-registered doctor. Discuss your results with your GP before making treatment decisions.

Sources

• Schuckit MA, "Recognition and management of withdrawal delirium (delirium tremens)", New England Journal of Medicine, 2014 (PMID 25427113)
• Jesse S, Bråthen G, Ferrara M et al., "Alcohol withdrawal syndrome: mechanisms, manifestations, and management", Acta Neurologica Scandinavica, 2017 (PMID 27586815)
• Wood E, Albarqouni L, Tkachuk S et al., "Clinical management of the alcohol withdrawal syndrome", Addiction, 2022 (PMID 34288186)
• Andresen-Streichert H, Müller A, Glahn A et al., "Alcohol Biomarkers in Clinical and Forensic Contexts", Deutsches Ärzteblatt International, 2018 (PMID 29807559)
• Bertol E, Vaiano F, Boscolo-Berto R et al., "Hair ethyl glucuronide and serum carbohydrate deficient transferrin for the assessment of relapse in alcohol-dependent patients", Clinical Biochemistry, 2016 (PMID 26851349)
• RIVM, figures and context on alcohol use in the Netherlands (rivm.nl)
• Thuisarts.nl, information on cutting down and stopping alcohol (thuisarts.nl)