Opioid withdrawal is what happens when someone who has been taking opioids regularly stops or cuts back. The body has adjusted to the drug, and without it, the nervous system goes into overdrive. It is miserable — people often compare it to the worst flu of their life — and while it is rarely dangerous in itself, what happens around it can be. This guide covers the symptoms, how long they last, and how medical treatment makes withdrawal safer and more bearable.
Opioid withdrawal symptoms
Symptoms tend to arrive in two waves.
Early symptoms
- Anxiety, restlessness and irritability
- Yawning
- Runny nose and watery eyes
- Sweating
- Muscle aches and joint pain
- Trouble sleeping
- Strong cravings
Later, fully developed symptoms
- Nausea, vomiting and diarrhea
- Stomach cramps
- Goosebumps and chills
- Dilated pupils
- Fast heartbeat and raised blood pressure
- Muscle twitching
- Fever
These lists follow the symptoms described in SAMHSA’s clinical guidance on opioid use disorder (TIP 63) and the StatPearls review of opioid withdrawal.
How long does opioid withdrawal last?
It depends mostly on how long the opioid stays in the body. Short-acting opioids leave quickly, so withdrawal starts sooner and ends sooner. Long-acting opioids like methadone produce a slower, longer withdrawal.
| Type of opioid | Withdrawal fully developed | Typical duration |
|---|---|---|
| Short-acting — heroin, fentanyl, oxycodone, hydrocodone | 1–3 days after the last dose | About 7–10 days |
| Long-acting — methadone, extended-release formulations | 72–96 hours after the last dose | 14 days or more |
Source: SAMHSA, TIP 63. Individual timelines vary.
For heroin, the first symptoms usually begin 8–12 hours after the last dose, and the most intense symptoms typically ease within 3–5 days (SAMHSA TIP 45), with milder symptoms lingering longer.
Fentanyl withdrawal
Fentanyl is short-acting, so it broadly follows the short-acting timeline. In practice, people who use fentanyl regularly can have less predictable withdrawal, and doctors take extra care when starting buprenorphine (see precipitated withdrawal below).
Symptoms that linger
After the physical symptoms fade, some people have anxiety, low mood, poor sleep and cravings for weeks or months. SAMHSA describes this as protracted withdrawal. It’s one reason relapse often happens after detox rather than during it.
Is opioid withdrawal dangerous?
Uncomplicated opioid withdrawal is rarely life-threatening on its own, unlike alcohol or benzodiazepine withdrawal. But there are real risks:
- Dehydration. Days of vomiting and diarrhea can cause dangerous fluid and electrolyte loss, especially for older adults, people who are pregnant, and anyone with heart or kidney problems.
- Overdose after withdrawal. This is the biggest danger. Tolerance falls quickly — HHS guidance notes it can take as little as a week. Going back to a previous amount after a few days or weeks off can be fatal, particularly with fentanyl in the drug supply. See the signs of an overdose and what to do.
- Relapse. The misery of withdrawal is a powerful pull back to using, which is why trying to “tough it out” at home so often fails.
If you’re pregnant, don’t stop opioids suddenly without medical advice.
How medical detox treats opioid withdrawal
Withdrawal can be managed. The aim is to keep the person safe and comfortable enough to move into ongoing treatment.
Medications for opioid use disorder
- Buprenorphine (often as Suboxone) eases withdrawal and cravings. Since 2023, any clinician with a standard DEA registration can prescribe it — the old “X-waiver” requirement was removed. Read more about how Suboxone works.
- Methadone is a long-acting opioid medication dispensed through certified opioid treatment programs.
- Naltrexone blocks opioids’ effects. It can only be started once someone is fully off opioids — typically 7–10 days after short-acting opioids and 10–14 days after long-acting ones (TIP 63).
Medications that ease symptoms
- Lofexidine (Lucemyra) became, in 2018, the first FDA-approved non-opioid medication for opioid withdrawal symptoms.
- Clonidine is also commonly used to reduce symptoms such as anxiety, sweating and agitation.
- Other medications can treat nausea, diarrhea, cramps and sleep problems.
Precipitated withdrawal
Buprenorphine binds to opioid receptors very strongly. If it’s taken while other opioids are still active, it can knock them off the receptors and trigger sudden, severe withdrawal. Clinicians usually avoid this by waiting until the person is in moderate withdrawal before the first dose, often measured with the Clinical Opiate Withdrawal Scale (COWS). Some now use low-dose starting methods instead. This is one of the clearest reasons to start buprenorphine under medical supervision rather than on your own.
Tru Dallas Detox provides medically supervised detox and medication-assisted treatment.
Signs of opioid addiction
Withdrawal on its own doesn’t mean someone is addicted. Anyone who takes opioids daily for a while — including people using them exactly as prescribed — can become physically dependent. NIDA distinguishes addiction as compulsive drug seeking and use despite harmful consequences.
Clinicians diagnose opioid use disorder using 11 criteria. Two or more within a 12-month period indicates the disorder — mild (2–3), moderate (4–5) or severe (6 or more). The criteria include:
- Taking more, or for longer, than intended
- Wanting to cut down but not being able to
- Spending a lot of time getting, using or recovering from opioids
- Cravings
- Falling behind at work, school or home
- Continuing despite problems in relationships
- Giving up activities that used to matter
- Using in physically dangerous situations
- Continuing despite physical or mental health problems caused or worsened by opioids
- Tolerance — needing more for the same effect
- Withdrawal when stopping
Tolerance and withdrawal don’t count toward the diagnosis for someone taking opioids only under appropriate medical supervision (TIP 63). Other outward signs families notice include running out of prescriptions early, “doctor shopping”, pinpoint pupils, nodding off, and money or valuables going missing.
Short-term effects of opioids
Opioids relieve pain and can cause euphoria, drowsiness, constipation, nausea and slowed breathing. The slowed breathing is what makes them deadly in overdose, especially when combined with alcohol, benzodiazepines or other sedatives.
How to taper off opioids safely
If you take prescribed opioids and want to stop, don’t stop suddenly. The CDC’s 2022 guideline says opioid therapy should not be discontinued abruptly, and doses shouldn’t be reduced rapidly from high levels.
A taper plan should be made with your prescriber. As a general guide, HHS/CDC clinician guidance notes that slower tapers — around 10% per month or slower — are often better tolerated, especially after more than a year of use. Faster tapers may suit shorter periods of use. Tapering isn’t right for everyone, and it should be adjusted based on how you’re coping.
If you’re using opioids that weren’t prescribed, a self-managed taper is much harder: the supply is unpredictable and often contains fentanyl. Medical detox with buprenorphine or methadone is usually the safer route.
Getting help
You don’t have to go through withdrawal alone, and you don’t have to have everything figured out before you call. Our admissions team answers 24 hours a day at (866) 971-7393, or you can check your coverage online.
Frequently asked questions
What is the worst day of opioid withdrawal?
For short-acting opioids like heroin or oxycodone, symptoms are usually at their worst within the first one to three days. For methadone, the peak comes later and the whole process lasts longer.
Can opioid withdrawal kill you?
Uncomplicated opioid withdrawal is rarely fatal by itself. The serious risks are severe dehydration and, most importantly, overdose if someone uses again after their tolerance has dropped.
How can I ease withdrawal at home?
The safest option is medical treatment. Medications like buprenorphine can dramatically reduce symptoms and cravings. If you’re waiting for care, stay hydrated, keep naloxone nearby, and don’t use alone.
Is physical dependence the same as addiction?
No. Dependence means your body has adapted to the drug and will react when it stops. Addiction involves compulsive use despite harm. The two often overlap, but not always.
Last updated: October 2026. Medically reviewed by Mitchell Naficy, MD, Medical Director at Tru Dallas Detox & Recovery Center (Texas Medical Board license W1860), October 2026. This page is general information, not medical advice. If someone isn’t breathing or can’t be woken, call 911.
