Detox Symptoms: What to Expect Hour by Hour

Detox symptoms follow a predictable timeline, from 6 hours to a week. What to expect, what staff do about each one, and when detox needs medical supervision.

Detox symptoms usually start within 6 to 12 hours of the last drink or dose, peak between 24 and 72 hours, and settle within a week for most people. What you feel depends on the substance, how long you have used it and how much.

Most detox symptoms are miserable rather than dangerous. The exceptions matter: alcohol, benzodiazepines and GHB can produce seizures and delirium, which is why those substances should never be stopped abruptly at home.

This article covers what detox actually feels like day by day and what a clinical team does about each symptom. For the medical detail on withdrawal itself, see our guide to symptoms of withdrawal.

What Detox Is

Detox is the process of clearing a substance from your body while the symptoms of stopping are managed. It is not treatment for addiction. It is what makes treatment possible, by getting the body through the risky part first.

A supervised detox does two things. It keeps you safe through the risky window, and it makes the experience bearable enough that you do not give up on day two. People rarely relapse during detox because they lack willpower. They relapse because the symptoms became unmanageable and using was the fastest way to stop them.

Detox Symptoms Hour by Hour

The timeline below covers alcohol, which is the most common and one of the most dangerous. It sets out what you feel at each stage and what a clinical team is doing about it. For the symptoms themselves in more detail, including seizure and delirium risk, see symptoms of withdrawal. Opioid and benzodiazepine timelines differ and are covered further down.

Time since last drink	What you feel	What the clinical team does
6 to 12 hours	The first shakes, sweating and rising anxiety	Baseline observations, first medication dose, fluids and thiamine
12 to 24 hours	Symptoms build. Sleep becomes almost impossible	Symptom scoring every few hours, medication adjusted to what you present
24 to 48 hours	The hardest stretch for most people	Seizure precautions in place, observations increased, doctor on call
48 to 72 hours	Symptoms plateau, then begin to turn	Daily doctor review, immediate escalation if confusion or fever appear
3 to 7 days	Appetite and sleep start returning	Medication tapered down, focus shifts to getting you into treatment
Weeks 2 to 6	Mood and sleep still uneven, cravings come in waves	No longer detox. This is where therapy and aftercare do the work

That last row matters more than people expect. The physical detox ends within a week, but sleep and mood take considerably longer to normalise, and that gap is where a lot of early relapse happens.

Alcohol Detox Symptoms

Alcohol detox symptoms are the ones most people underestimate. Early on you get anxiety, shaking hands, sweating, nausea and an inability to sleep. That much is unpleasant but manageable.

The concern is what can follow. A minority of drinkers develop withdrawal seizures in the first two days, and a smaller group develop delirium tremens after 48 hours. Both are medical emergencies, and both are largely preventable when the detox is medically supervised from the start.

Risk rises with each previous withdrawal. Someone who has detoxed and relapsed several times faces a higher chance of seizing than someone stopping for the first time, even at the same drinking level.

Opioid Detox Symptoms

Opioid detox, whether from heroin, codeine or prescription painkillers, is severe but rarely life-threatening. Expect muscle and bone aches, stomach cramps, diarrhoea, vomiting, runny eyes and nose, goosefleshy skin and profound restlessness.

Symptoms typically begin 8 to 24 hours after the last dose for short-acting opioids and peak around day two or three. Longer-acting opioids such as methadone start later and last longer, sometimes two weeks or more.

The danger with opioid detox is not the withdrawal itself but what comes after:

Tolerance drops fast during detox, so a return to a previously normal dose can be fatal. That is the single most important reason to complete a detox properly rather than abandon it halfway.

Benzodiazepine Detox Symptoms

Benzodiazepine detox is the one that most often goes wrong at home. Symptoms include rebound anxiety far worse than the original, insomnia, muscle spasms and abnormal skin sensations. Serious cases bring seizures and psychosis.

Benzodiazepines are not stopped abruptly. They are tapered instead, sometimes over weeks, with the taper adjusted as symptoms present. Anyone who has been on regular benzodiazepines for months should not attempt this without a doctor, regardless of the dose.

Our guide to drugs you should not quit cold turkey covers the full list.

When Detox Symptoms Become an Emergency

Get medical help immediately for any of the following:

• A seizure, or a period of unresponsiveness
• Confusion, disorientation or not knowing where you are
• Hallucination, seeing, hearing or feeling things that are not there
• A fever alongside a racing or irregular heartbeat
• Uncontrolled vomiting, or signs of dehydration
• Chest pain, or severe agitation that will not settle

These are not symptoms to wait out. Delirium tremens is fatal in a meaningful proportion of untreated cases, and it develops in people who were managing reasonably well the day before.

What a Supervised Detox Does About Each Symptom

A medically supervised detox is not simply a bed in a quiet room. Symptoms are anticipated and medicated rather than endured.

For alcohol, that usually means benzodiazepines on a tapering schedule to prevent seizures and delirium, alongside fluids, thiamine and monitoring of pulse, blood pressure and temperature.

For opioids, it means medication for cramps, nausea, diarrhoea and sleep, sometimes with a substitute opioid tapered down.

For benzodiazepines, it means a structured taper rather than a stop.

At Changes, detox runs at our Northcliff facility with nursing and doctor-led oversight. Clients are reviewed daily, and medication is adjusted as symptoms change rather than set once on admission.

Can You Detox at Home?

For cannabis, stimulants and most first-time opioid users, home detox is uncomfortable but not usually dangerous. For alcohol, benzodiazepines and GHB, it can kill you, and the people most likely to try it are the ones most at risk.

The honest test is not how motivated you feel. It is whether you drink daily, whether you have had withdrawal symptoms before, whether you have any heart or liver condition, and whether someone will be with you. If more than one of those points the wrong way, detox belongs in a facility.

We cover the comparison in more detail in alcohol detox at home versus rehab.

What Happens After Detox

Detox clears the substance. It does not address why the substance was being used, which is why detox on its own has such a poor track record.

Treatment starts once you are stable, usually in primary care, where the therapeutic work begins. Most schemes fund detox and inpatient treatment together as a single admission, so the two do not need to be arranged separately.

Get an Assessment

Not sure whether your detox needs supervision? An assessment takes one conversation and it is where we work out the risk honestly, including whether you can safely do this at home.

Call 081 444 7000, or check your medical aid cover and we will confirm what your scheme funds before you are admitted.