Short answer: for most people, the hardest part of detox lasts 3 to 7 days, with symptoms usually peaking somewhere in the first 72 hours. But the full picture depends on the substance: alcohol and short-acting opioids tend to run a few days, while benzodiazepines can stretch over weeks. Here’s the substance-by-substance breakdown, plus a note on why “how long” isn’t the only question that matters.
When you’re facing detox, the timeline is the thing you want to know first: how many days until this is behind me? It’s a fair question, and an honest answer helps you prepare. Just know up front that these are typical ranges, not promises. Your own experience depends on what you’ve used, how long, your health, and whether you have medical support.
| Substance | Symptoms start | Peak | Acute phase eases |
|---|---|---|---|
| Alcohol | 6–24 hours | 24–72 hours | 5–7 days |
| Short-acting opioids (heroin) | 8–24 hours | 1–3 days | 5–7 days |
| Long-acting opioids / fentanyl | 12–48 hours | 3–5 days | 7–10 days |
| Benzodiazepines | 1–4 days | 1–2 weeks | 2–8 weeks (tapered) |
| Stimulants (cocaine, meth, Adderall) | Hours–1 day | 1–3 days | 1–2 weeks |
Alcohol detox timeline
Alcohol withdrawal often begins 6 to 24 hours after the last drink, starting with anxiety, shakiness, sweating, nausea, and trouble sleeping. The window that matters most is 24 to 72 hours, when symptoms peak and the risk of seizures and delirium tremens (DTs) is highest. DTs (marked by confusion, hallucinations, fever, and a racing heart) are a medical emergency. For most people the acute phase settles within 5 to 7 days, though sleep and mood can stay unsettled for a while after. Because of that seizure and DT risk, heavy alcohol use is one of the clearest cases for medical supervision rather than detoxing alone.
Opioid detox timeline
With short-acting opioids like heroin, withdrawal usually starts 8 to 24 hours after the last use, peaks within 1 to 3 days, and eases over roughly a week. Longer-acting opioids (methadone, and often fentanyl) start later (12 to 48 hours) and can run 10 days or more. Symptoms feel like a severe flu turned all the way up: muscle and bone aches, sweating and chills, stomach cramps, nausea, vomiting, and intense cravings. Opioid withdrawal is rarely dangerous on its own, but the cravings are powerful and the relapse-and-overdose risk afterward is serious, which is where medication-assisted treatment makes a real difference.
Benzodiazepine detox timeline
Benzodiazepines (Xanax, Ativan, Klonopin, Valium) have the longest and least predictable timeline. Symptoms can begin 1 to 4 days after the last dose depending on whether the drug is short- or long-acting, and a medically managed taper often stretches the process over several weeks. Like alcohol, abrupt benzo withdrawal can cause seizures, so this is never one to rush or attempt cold-turkey. A gradual, supervised taper is the safe path.
Stimulant detox timeline
Detox from cocaine, methamphetamine, or Adderall looks different. The physical symptoms are usually milder, but the “crash” (exhaustion, heavy sleep, big appetite, and a low, flat mood) sets in within hours to a day and can linger for one to two weeks. The main risk here is emotional: depression and even suicidal thoughts can surface, and they deserve real support rather than waiting them out alone.
When to get medical supervision: Some withdrawals are more dangerous than the timeline alone suggests. Don’t try to wait it out at home if you’ve been drinking heavily or using benzodiazepines (both carry a seizure risk), have a heart condition, are pregnant, have had severe withdrawal before, or are having any thoughts of self-harm. A short phone call can tell you what’s safe for your situation.
What changes your timeline
Two people detoxing from the same substance can have very different experiences. The biggest factors:
- How much, and how long. Higher doses over more years generally mean a longer, more intense process.
- The specific substance, and combinations. Long-acting drugs leave the body slowly, and using more than one substance complicates the timeline.
- Your body and health. Age, liver and kidney function, nutrition, and co-occurring medical or mental health conditions all play a role.
- Whether you have support. Medications given during a medically supervised detox in Massachusetts can ease symptoms and, for alcohol and benzodiazepines, prevent the dangerous complications that drag withdrawal out.
Two stages: acute withdrawal and PAWS
It helps to think of detox in two stages:
The intense, physical phase, with the symptoms in the table above. This is the stretch that medical detox is built to manage.
Milder, lingering effects like sleep trouble, mood swings, or low motivation as the brain re-balances. It’s normal, and it fades.
PAWS is one of the reasons early recovery feels hard even after detox is technically “done.” Knowing it’s coming helps you ride it out instead of mistaking it for failure. You can read more in our guide to withdrawal symptoms.
Why “how long” isn’t the whole story
It’s natural to focus on getting through the days. But detox only clears the substance from your body. It isn’t the finish line of recovery by itself. In fact, detox without follow-up treatment has high relapse rates, because the substance use disorder underneath hasn’t been addressed. That’s why a good detox flows straight into the next level of care, where the lasting work happens. If you’re curious what the days themselves look like, we walk through it in what to expect during medical detox.
Frequently asked questions
What’s the hardest day of detox?
For many substances, days two and three are the toughest. That’s when symptoms tend to peak. After that, the acute phase usually starts to ease.
Can I just detox at home and wait it out?
For some substances and mild cases it may be possible, but alcohol and benzodiazepine withdrawal can cause seizures, so judging that on your own is risky. A quick call with a clinical team can tell you whether home detox is safe for your situation.
Will detox get rid of my cravings?
Detox reduces the acute physical cravings, but cravings can return during PAWS and beyond. Ongoing treatment (therapy, support, and for opioids often medication) is what keeps them manageable long-term.
You don’t have to count the days alone
However long your detox takes, you don’t have to white-knuckle it. If you’re in Massachusetts, our team can give you a realistic sense of your timeline and what would make it safer and more comfortable. No pressure, no judgment. Verify your insurance in a few minutes, or call us at 855 732 4842 and just ask.
This article is for educational purposes and isn’t a substitute for medical advice. In a medical emergency, call 911; for mental-health crisis support, call or text 988.