For most people, the acute phase of alcohol detox takes about 3 to 7 days. Symptoms typically start within 6 to 12 hours after your last drink, peak between 24 and 72 hours, and gradually taper from there. But the full picture is more nuanced than a single number, because severity varies widely and some symptoms can linger for weeks or months after the acute phase ends.
The First 72 Hours
Alcohol withdrawal follows a fairly predictable pattern, though the intensity depends on how much and how long you’ve been drinking.
6 to 12 hours: The earliest symptoms show up surprisingly fast. Headache, mild anxiety, insomnia, nausea, and shakiness are common. Many people describe feeling jittery or “off” even before a full day has passed.
12 to 24 hours: Symptoms intensify. Tremors (the classic “shakes”) typically peak somewhere between 24 and 48 hours. Some people experience hallucinations, which can start within 12 to 24 hours and last up to two days. These can be visual, auditory, or tactile, and they don’t necessarily mean you’re in the most dangerous category of withdrawal.
24 to 72 hours: This is the window when symptoms are at their worst for most people. It’s also when the most serious complications can appear. Seizures are possible 6 to 48 hours after your last drink, with the highest risk at the 24-hour mark. If multiple seizures occur, they tend to cluster over several hours.
When Detox Becomes Dangerous
The complication that gets the most attention is delirium tremens, often called DTs. It typically begins 2 to 3 days after the last drink, though it can be delayed by more than a week. Peak intensity usually hits around 4 to 5 days after the last drink. DTs involve severe confusion, rapid heartbeat, fever, and heavy sweating. This is a medical emergency that requires professional monitoring.
Not everyone who goes through withdrawal will experience DTs. The risk is highest for people who have been drinking heavily for years, have gone through withdrawal before, or have other medical conditions on top of alcohol dependence. Previous withdrawal episodes actually sensitize the brain, making each subsequent round more likely to produce severe symptoms.
What Determines Your Timeline
Several factors push your detox experience toward the shorter, milder end or the longer, more severe end of the spectrum. The biggest ones are how much you drink daily, how many years you’ve been drinking, and whether you’ve been through withdrawal before. Someone who drinks a few beers a night for a year will have a very different experience than someone who has been consuming a fifth of liquor daily for a decade.
Your overall health matters too. Liver function plays an obvious role since that’s where alcohol is processed, but nutritional status, age, and co-existing mental health conditions all influence how your body handles the adjustment. Older adults and people with poor nutrition tend to have longer, more difficult withdrawals.
Clinicians use a standardized scoring system to gauge severity in real time. Scores below 8 to 10 indicate mild withdrawal that often doesn’t require medication. Scores between 8 and 15 suggest moderate withdrawal with noticeable physical symptoms like elevated heart rate and blood pressure. Scores above 15 signal severe withdrawal and the possibility of DTs. Your score can change hour to hour, which is why medically supervised detox involves frequent reassessment.
What Happens After the Acute Phase
Here’s the part that catches many people off guard: the acute withdrawal symptoms may resolve within a week, but a second wave of subtler symptoms can persist for months or even years. This is known as post-acute withdrawal, and it’s a recognized clinical condition involving prolonged neurological changes that outlast the initial detox.
The most common post-acute symptoms are mood swings, irritability, depression, anxiety, sleep problems, difficulty concentrating, and cravings. These aren’t just psychological. They reflect a brain that spent months or years adapting to the constant presence of alcohol and is now recalibrating without it. Sleep disruption is particularly stubborn and can last well beyond the point where other symptoms improve.
Post-acute withdrawal is one of the main reasons relapse rates are high in early recovery. The acute detox may feel like the hard part, but the weeks and months that follow require their own strategy. Ongoing support, whether through counseling, peer groups, or medication, addresses this longer timeline in a way that detox alone cannot.
Medical vs. At-Home Detox
Mild withdrawal can sometimes be managed on an outpatient basis with regular check-ins. But moderate to severe withdrawal, especially if you have a history of seizures, DTs, or heavy daily drinking, is safest in a medical setting where symptoms can be treated as they escalate. The unpredictable nature of the 24 to 72 hour window is the main reason: someone who seems stable at hour 12 can deteriorate quickly by hour 36.
In a supervised setting, detox typically takes 3 to 7 days for the acute phase, with most people feeling significantly better by day 5. Outpatient detox follows a similar biological timeline but involves daily or near-daily visits rather than round-the-clock monitoring. Either way, the physical symptoms of acute withdrawal are time-limited. What matters most is what comes next.