Short answer: Oxazepam is an intermediate-acting benzodiazepine for anxiety and alcohol withdrawal. It is a Schedule IV prescription medicine. Because it is cleared without the liver enzymes most benzodiazepines need and has no active metabolites, it is often chosen for older adults and people with liver disease.
Key takeaways
- What it is: Oxazepam is an intermediate-acting benzodiazepine and a Schedule IV controlled substance in the US.
- Main uses: Anxiety; alcohol withdrawal.
- Timing: effects start in 1 to 2 hours and last 6 to 8 hours.
- Most dangerous mix: Opioids (oxycodone, hydrocodone, fentanyl, heroin), which can cause profound sedation, slowed breathing, coma, death.
- Naloxone: it does not reverse this drug, but give it whenever opioids could be involved.
- Dependence risk: High.
- Legal route: only with a prescription from a DEA-registered clinician, filled by a licensed pharmacy.
What is oxazepam?
Oxazepam treats anxiety, including anxiety with depression, and acute alcohol withdrawal.
It is itself a metabolite of diazepam. It is processed by glucuronidation rather than oxidation, a pathway that is relatively preserved in liver disease and aging, so it builds up less than long-acting benzodiazepines.
Quick facts
| Fact | Oxazepam |
|---|---|
| Generic name | Oxazepam |
| Brand names | Serax (discontinued); generic only |
| Drug class | Intermediate-acting benzodiazepine |
| US legal status | Schedule IV, prescription only |
| Approved uses | Anxiety disorders; anxiety with depression; acute alcohol withdrawal |
| Forms | Capsules (10, 15, 30 mg) |
| Onset | 1 to 2 hours (slow) |
| Half-life | About 5 to 15 hours |
| Broken down by | Glucuronidation, without active metabolites |
How long does oxazepam last?
- Starts working: 1 to 2 hours
- Effects last: 6 to 8 hours
- Half-life: About 5 to 15 hours
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 oxazepam?
The FDA requires boxed warnings, its strongest, on oxazepam products, including:
- Use with opioids can cause profound sedation, slowed breathing, coma, and death.
- Abuse, misuse, and addiction, which can lead to overdose and death, especially with alcohol, opioids, or other drugs.
- Physical dependence: stopping suddenly or reducing the dose quickly can cause life-threatening withdrawal reactions, including seizures.
Common side effects include drowsiness, dizziness, and unsteadiness.
Slow onset: because it is absorbed slowly, it is less suited to rapid relief of panic, and people may be tempted to take extra doses before the first has worked.
What should you never mix with oxazepam?
| Combined with | What happens | Label guidance |
|---|---|---|
| Opioids (oxycodone, hydrocodone, fentanyl, heroin) | Profound sedation, slowed breathing, coma, death | Boxed warning; avoid unless no alternative |
| Alcohol | Deeper sedation, blackouts, slowed breathing | Avoid |
| Other sedatives (sleep medicines, gabapentinoids, muscle relaxants, antihistamines) | Additive drowsiness and impaired coordination | Use caution |
Check any combination with the DoseUses combination checker or ask a pharmacist.
What are the signs of an oxazepam overdose, and what should you do?
Oxazepam overdose causes deep drowsiness, confusion, poor coordination, slowed reflexes, and coma. With opioids or alcohol, breathing can stop.
If someone may have overdosed
- Call 911 if the person is unresponsive, hard to wake, or breathing slowly.
- For advice when the person is awake and stable, call Poison Help at 1-800-222-1222 (US, free, 24 hours).
- If opioids could be involved, including pills not from a pharmacy, give naloxone if you have it. Naloxone does not reverse oxazepam, but it will not harm the person.
- Stay with the person and place them on their side if they are drowsy or vomiting.
What is oxazepam withdrawal like, and how long does it last?
People who take oxazepam regularly, even as prescribed, can become physically dependent within weeks.
- Days 1 to 3Symptoms beginRebound anxiety, insomnia, restlessness, sweating, and tremor.
- Weeks 1 to 4Acute withdrawalPanic, irritability, muscle pain, nausea, sensitivity to light and sound, and in severe cases seizures or delirium.
- MonthsProtracted symptoms in some peopleA minority have lingering anxiety, poor sleep, low mood, or tingling that can last weeks to more than 12 months.
See the withdrawal timelines and the full oxazepam withdrawal guide.
Is oxazepam legal?
In the United States, oxazepam is a Schedule IV 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: a Schedule IV prescription can be refilled up to five times within six months of the date it was written. After that, a new prescription is needed.
- 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 C; prescription only |
| Canada | Schedule IV of the Controlled Drugs and Substances Act |
| Australia | Schedule 4 prescription medicine |
| International | Schedule IV of the 1971 Convention on Psychotropic Substances |
Frequently asked questions about oxazepam
Why is oxazepam used in liver disease?
It has no active metabolites and is cleared by a pathway less affected by liver disease, so it is less likely to accumulate.
Is oxazepam a strong benzodiazepine?
It is relatively mild per milligram: about 15 to 30 mg is roughly equivalent to 5 mg of diazepam.
How fast does oxazepam work?
It is absorbed slowly and takes 1 to 2 hours to work.
Can oxazepam be used for sleep?
It is not approved for insomnia, though it is sometimes prescribed for sleep in some countries.
Is oxazepam addictive?
Yes. Like other benzodiazepines, it can cause dependence and addiction.
Sources
- oxazepam prescribing information, DailyMed, US National Library of Medicine.
- FDA warns about serious risks and death when combining opioid pain or cough medicines with benzodiazepines, US Food and Drug Administration, 2016.
- FDA requiring Boxed Warning updated to improve safe use of benzodiazepine drug class, US Food and Drug Administration, 2020.
- Joint Clinical Practice Guideline on Benzodiazepine Tapering, American Society of Addiction Medicine, 2025.
- Controlled Substance Schedules, DEA Diversion Control Division.
- 21 CFR 1306.22, Refilling of prescriptions (Schedules III and IV), Electronic Code of Federal Regulations.
- Prescribing controlled substances via telehealth, US Department of Health and Human Services.
- BeSafeRx: Your Source for Online Pharmacy Information, US Food and Drug Administration.
This guide summarizes the sourced DoseUses Oxazepam profile, written from FDA labels, DEA rules, and federal health agencies. It is educational and is not medical advice. Last updated October 5, 2026.
