Short answer: Oxymorphone is a strong prescription opioid for severe pain, roughly twice as potent as oxycodone by mouth. It is a Schedule II controlled substance. The extended-release brand Opana ER was taken off the market in 2017 after misuse by injection fueled an HIV outbreak.
Key takeaways
- What it is: Oxymorphone is an opioid agonist and a Schedule II controlled substance in the US.
- Main uses: Severe pain.
- Timing: effects start in 30 to 45 minutes and last 4 to 6 hours (immediate release).
- Most dangerous mix: Benzodiazepines (alprazolam, diazepam, clonazepam), which can cause profound sedation, slowed breathing, coma, death.
- Naloxone: it reverses an overdose.
- Dependence risk: High.
- Legal route: only with a prescription from a DEA-registered clinician, filled by a licensed pharmacy.
What is oxymorphone?
Oxymorphone is approved for adults with acute or chronic pain severe enough to require an opioid when other treatments are not enough. It is also a metabolite of oxycodone, formed in small amounts in the liver.
In 2017 the FDA asked the maker of the reformulated Opana ER to remove it from the market. Despite an abuse-deterrent coating, people crushed and injected it, which was linked to an HIV and hepatitis C outbreak in Scott County, Indiana, and to a rare blood disorder called thrombotic microangiopathy.
Quick facts
| Fact | Oxymorphone |
|---|---|
| Generic name | Oxymorphone hydrochloride |
| Brand names | Opana (immediate release); Opana ER was withdrawn in 2017 |
| Drug class | Semi-synthetic opioid agonist |
| US legal status | Schedule II, prescription only |
| Approved uses | Pain severe enough to require an opioid when other treatments are inadequate |
| Forms | Immediate-release tablets; extended-release generics |
| Onset | 30 to 45 minutes |
| Half-life | About 7 to 9 hours |
| Broken down by | The liver, mainly by glucuronidation (little CYP450 involvement) |
How long does oxymorphone last?
- Starts working: 30 to 45 minutes
- Effects last: 4 to 6 hours (immediate release)
- Half-life: About 7 to 9 hours
Its half-life is 7 to 9 hours. Urine tests usually detect it for 1 to 4 days, but standard opiate screens may miss it, so specific tests are used.
Timing varies with the dose, the form, how it is taken, liver and kidney function, age, and other drugs taken at the same time.
What are the biggest risks of oxymorphone?
The FDA requires boxed warnings, its strongest, on oxymorphone products, including:
- Addiction, abuse, and misuse, which can lead to overdose and death.
- Life-threatening slowed breathing, especially when starting treatment or after a dose increase.
- Accidental ingestion, especially by children, can cause a fatal overdose.
- Use with benzodiazepines or other central nervous system depressants, including alcohol, can cause profound sedation, slowed breathing, coma, and death.
Common side effects include nausea, constipation, drowsiness, dizziness, itching, and sweating.
Food and alcohol: food raises blood levels by about 50%, which is why it is taken on an empty stomach. Alcohol can sharply increase levels and must be avoided.
Injection harms: injecting tablets designed to be swallowed can cause HIV and hepatitis C transmission, serious infections, and damage to small blood vessels and kidneys.
What should you never mix with oxymorphone?
| Combined with | What happens | Label guidance |
|---|---|---|
| Benzodiazepines (alprazolam, diazepam, clonazepam) | Profound sedation, slowed breathing, coma, death | Boxed warning; avoid unless no alternative |
| Alcohol | Stronger sedation and slowed breathing | Avoid |
| Gabapentin, pregabalin, sleep medicines, muscle relaxants | Additive sedation and breathing problems | Use caution; lower doses |
| MAO inhibitors (within 14 days) | Serotonin syndrome or opioid toxicity | Not recommended |
| Mixed agonist-antagonists (butorphanol, nalbuphine, pentazocine) and buprenorphine | Reduced pain relief; can trigger withdrawal | Avoid |
| Anticholinergic drugs | Severe constipation, urinary retention | Monitor |
Check any combination with the DoseUses combination checker or ask a pharmacist.
What are the signs of an oxymorphone overdose, and what should you do?
Oxymorphone overdose causes extreme sleepiness, pinpoint pupils, slow or stopped breathing, limp muscles, cold clammy skin, and unconsciousness.
If someone may have overdosed
- Call 911 if the person is unresponsive, cannot be woken, has blue or gray lips, or is breathing slowly or not at all.
- Give naloxone (Narcan or a generic nasal spray, sold without a prescription) into one nostril. If there is no response after 2 to 3 minutes, give another dose.
- If you are trained, give rescue breaths. Otherwise place the person on their side so they do not choke.
- Stay with them. Naloxone can wear off before oxymorphone does, so the overdose can return even after the person wakes up.
- Most states have Good Samaritan laws that protect people who call 911 for an overdose from some drug charges.
What is oxymorphone withdrawal like, and how long does it last?
People who take oxymorphone regularly for more than a few weeks become physically dependent, even when they take it exactly as prescribed. Dependence is not the same as addiction, but it means stopping suddenly causes withdrawal.
- 8 to 24 hoursEarly symptomsAnxiety, restlessness, yawning, sweating, runny nose, watery eyes, and muscle aches.
- Days 1 to 3Peak withdrawalDiarrhea, stomach cramps, nausea and vomiting, goosebumps, dilated pupils, fast heartbeat, and strong cravings. Rarely dangerous in healthy adults, but dehydration can be serious.
- Days 5 to 10, then weeksLingering symptomsPoor sleep, low mood, low energy, and cravings can continue for weeks. Tolerance falls quickly, which raises the risk of overdose if use restarts.
See the withdrawal timelines and the full oxymorphone withdrawal guide.
Is oxymorphone legal?
In the United States, oxymorphone is a Schedule II controlled substance. The only legal way to get it is with a prescription from a clinician registered with the Drug Enforcement Administration (DEA), filled by a licensed pharmacy. Depending on state law, that can be a physician, nurse practitioner, or physician assistant.
- Refills: Schedule II prescriptions cannot be refilled. A prescriber can issue several prescriptions at once, each dated with the earliest fill date, for up to a 90-day supply.
- Telehealth: federal flexibilities let DEA-registered clinicians prescribe Schedule II to V medicines after a telemedicine visit, without a prior in-person exam, through December 31, 2026. A permanent DEA rule was under final review in late 2026. State rules can be stricter.
- Monitoring: prescribers and pharmacists in most states check a prescription drug monitoring program, a database of controlled-substance prescriptions, before prescribing or dispensing.
Outside the United States
| Country | Status |
|---|---|
| United Kingdom | Class A |
| Canada | Schedule I of the Controlled Drugs and Substances Act |
| Australia | Schedule 8 controlled drug |
| International | Schedule I of the 1961 Single Convention on Narcotic Drugs |
Frequently asked questions about oxymorphone
Is oxymorphone stronger than oxycodone?
Yes. By mouth, oxymorphone is about twice as potent as oxycodone per milligram, so doses are not interchangeable.
Why was Opana ER taken off the market?
In 2017 the FDA concluded that the risks of the reformulated Opana ER, mainly from people injecting it, outweighed its benefits, and asked the maker to stop selling it.
Should oxymorphone be taken with food?
No. The label says to take it on an empty stomach, because food raises blood levels and can increase side effects.
How long does oxymorphone stay in your system?
Its half-life is 7 to 9 hours. Urine tests usually detect it for 1 to 4 days, but standard opiate screens may miss it, so specific tests are used.
Can naloxone reverse an oxymorphone overdose?
Yes. Naloxone reverses oxymorphone, but repeat doses may be needed, especially with extended-release tablets.
Sources
- Opana (oxymorphone) prescription information, DailyMed, US National Library of Medicine.
- FDA requests removal of Opana ER for risks related to abuse, US Food and Drug Administration, 2017.
- FDA warns about serious risks and death when combining opioid pain or cough medicines with benzodiazepines, US Food and Drug Administration, 2016.
- Information about naloxone and nalmefene, US Food and Drug Administration.
- CDC Clinical Practice Guideline for Prescribing Opioids for Pain, 2022, Centers for Disease Control and Prevention, MMWR.
- Controlled Substance Schedules, DEA Diversion Control Division.
- 21 CFR 1306.12, Refilling prescriptions; issuance of multiple prescriptions (Schedule II), Electronic Code of Federal Regulations.
- Prescribing controlled substances via telehealth, US Department of Health and Human Services.
This guide summarizes the sourced DoseUses Oxymorphone profile, written from FDA labels, DEA rules, and federal health agencies. It is educational and is not medical advice. Last updated October 5, 2026.
