Most opioid withdrawal doesn’t require an ER visit — but some specific signs genuinely do, and knowing the difference in advance is more useful than trying to figure it out while it’s happening.
Go to the ER (or call 911) if you experience:
- Inability to keep any fluids down for 24 hours or more, or signs of significant dehydration (severe dizziness, very dark urine, confusion, not urinating)
- Vomiting blood, or blood in stool
- Chest pain or difficulty breathing
- Seizures — this is not typical of opioid withdrawal alone and suggests alcohol or benzodiazepine withdrawal may also be involved, which is a medical emergency [link to polysubstance withdrawal articles]
- Confusion, hallucinations, or severe disorientation — also atypical for opioid withdrawal alone and warrants urgent evaluation
- Thoughts of suicide or self-harm — call or text 988, or go to the ER if you’re in immediate danger
- Signs of overdose after any return to use — this overrides everything else on this page; call 911 and use naloxone if available [link to overdose response tool]
- You’re pregnant — untreated withdrawal during pregnancy needs direct medical involvement, not a wait-and-see approach
What doesn’t necessarily require the ER, but does warrant calling a doctor
- Withdrawal symptoms that feel unmanageable even though none of the above apply
- Uncertainty about whether what you’re feeling is normal withdrawal or something else
- A pre-existing heart, liver, or kidney condition and you’re planning to withdraw at home
A practical note on going to the ER for withdrawal
Emergency departments are increasingly equipped to start buprenorphine directly for opioid use disorder [link to ED-initiated buprenorphine article] — going to the ER during withdrawal isn’t just about ruling out an emergency, it can also be a legitimate entry point into treatment itself.
Medically reviewed by [pending]. Sources: ASAM National Practice Guideline, SAMHSA TIP 63.