Detox in rehab typically lasts 3 to 10 days for most substances, though some require weeks or even months of medically supervised tapering. The exact timeline depends on what substance you’re detoxing from, how long and how heavily you’ve been using, and your overall health. Here’s what to realistically expect.
What Happens During Detox
Medical detox follows three general stages: evaluation, stabilization, and transition to treatment. During evaluation, the medical team assesses your health history, substance use patterns, and any co-occurring mental health conditions. This lets them build a detox plan specific to your situation rather than applying a generic protocol.
Stabilization is the most intensive phase. This is when withdrawal symptoms peak and when you’ll receive the most hands-on medical support, including medications to manage discomfort, prevent dangerous complications, and help you sleep. Once you’re physically and mentally stable, you transition into the next phase of treatment, whether that’s inpatient rehab, outpatient therapy, or another structured program. Detox itself is not treatment for addiction. It’s the step that gets your body ready for treatment.
Alcohol Detox: 3 to 7 Days
Alcohol withdrawal is one of the most medically serious forms of detox. Mild symptoms like headache, anxiety, and insomnia typically appear within 6 to 12 hours of your last drink. Symptoms peak between 24 and 72 hours, which is also the window of highest risk for seizures (24 to 48 hours) and delirium tremens (48 to 72 hours). Most people with mild to moderate withdrawal see their symptoms begin to resolve within that same 24 to 72 hour peak window.
In a rehab setting, alcohol detox generally takes 5 to 7 days, though the first 3 days are the hardest. Medical staff monitor withdrawal severity closely and use medications to prevent seizures, reduce anxiety, control nausea, and manage sleep disruption. People with a long history of heavy drinking or previous complicated withdrawals may need closer monitoring and a longer stabilization period.
Opioid Detox: 5 to 14 Days
The timeline for opioid detox depends heavily on whether you were using short-acting or long-acting opioids. For short-acting opioids like heroin or fentanyl, physical withdrawal symptoms start 6 to 12 hours after the last dose and last roughly 5 days. Longer-acting opioids like methadone produce a slower onset of withdrawal but stretch the process out over 10 to 14 days or more.
Most rehab programs plan for 7 to 10 days of opioid detox. The current standard of care favors starting patients on maintenance medications like buprenorphine or methadone during detox rather than simply tapering off and sending people into treatment unmedicated. These medications reduce cravings, ease withdrawal, and significantly lower the risk of relapse and overdose. If your rehab program uses this approach, stabilization on the medication happens during the detox phase, and you continue taking it through treatment and beyond.
Benzodiazepine Detox: Weeks to Months
Benzodiazepine detox is the outlier. Abruptly stopping after daily use of more than one month is potentially dangerous, and withdrawal can be severe or life-threatening. For this reason, benzo detox almost always involves a slow, gradual taper rather than a short detox stay.
Some programs use a fairly rapid taper of 8 to 12 weeks, with the option to slow down if withdrawal symptoms become unmanageable. Others take a much longer approach. Tapers lasting 6 months or more are common, and even tapers stretching one to two years can be successful for some patients. The pacing depends on how long you’ve been taking benzodiazepines, the dose, and how your body responds to each reduction. With short-acting benzodiazepines, rebound symptoms can appear between doses, which makes the process trickier.
Because of these longer timelines, benzo detox often doesn’t fit neatly into a traditional rehab stay. You may begin the taper in an inpatient setting and continue it on an outpatient basis over several months.
Stimulant Detox: 1 to 3 Weeks
Withdrawal from stimulants like cocaine and methamphetamine looks different from alcohol or opioid withdrawal. There’s less physical danger, but the psychological symptoms are intense. The initial “crash” phase brings extreme fatigue, depression, and increased appetite, and it typically lasts a few days. The broader withdrawal period, including low energy, depression, anxiety, paranoia, and strong cravings, can persist for weeks or months.
In a rehab setting, stimulant detox usually takes 1 to 3 weeks. There are no standard medications to manage stimulant withdrawal the way there are for alcohol or opioids, so treatment focuses on rest, nutrition, emotional support, and managing specific symptoms like sleep problems or anxiety.
Why Some People Need Longer
Several factors push detox beyond the typical ranges. People who used multiple substances simultaneously face overlapping withdrawal timelines that extend the process. Those with underlying medical conditions or mental health disorders often need extra stabilization time. A longer or heavier history of use generally means more severe withdrawal and a longer detox.
Your body composition, liver function, age, and general nutrition all play a role too. Someone who has been through withdrawal before may actually experience more intense symptoms each time, a phenomenon called kindling, which is especially relevant for alcohol withdrawal.
After Acute Detox: What Lingers
Even after the acute detox phase wraps up, many people experience lingering symptoms known as post-acute withdrawal. These include mood swings, sleep disturbances, difficulty concentrating, irritability, and low energy. This phase typically lasts 6 to 24 months, with symptoms coming in waves rather than staying constant.
This is one reason detox alone rarely leads to lasting recovery. The weeks and months after detox are when structured treatment, whether residential rehab, outpatient programs, or ongoing medication, makes the biggest difference. Detox clears the substance from your system. Everything that follows addresses why you were using it in the first place.