Oxazepam Drug Interactions: What to Avoid and What to Tell Your Doctor

Oxazepam has one of the most important drug interaction concerns of any common medication — particularly with opioids and other substances that depress the central nervous system. Understanding these interactions could literally save your life. Here's what every patient on Oxazepam needs to know.

The Boxed Warning: Oxazepam + Opioids = Dangerous Combination

Oxazepam carries the FDA's highest-level warning — a boxed warning — about combining benzodiazepines with opioids. Taking both together can cause profound sedation, respiratory depression (stopped breathing), coma, and death.

Opioids that should never be combined with Oxazepam without explicit medical supervision include:

• Oxycodone (OxyContin, Percocet)
• Hydrocodone (Vicodin, Norco)
• Morphine
• Fentanyl (including patches, lozenges, and nasal spray)
• Codeine (including cough syrups)
• Tramadol
• Buprenorphine (Suboxone, Subutex)

If you are prescribed both an opioid and Oxazepam, your prescribers must all be aware of both medications. Never start one without telling the doctor about the other. Both you and people you live with should know the signs of respiratory depression: unusual sleepiness, slowed breathing, lips turning blue, inability to wake the person up.

Alcohol: Never Combine With Oxazepam

Alcohol is a central nervous system depressant, just like Oxazepam. Combining them creates an additive and unpredictable effect on the brain. Even a small amount of alcohol while taking Oxazepam can dramatically increase sedation, impair judgment, increase memory blackouts, and in severe cases cause respiratory depression, coma, or death. This combination is never safe.

Sodium Oxybate (GHB, Xyrem): Avoid Entirely

Sodium oxybate (the prescription medication Xyrem, as well as the illicit drug GHB) has a major interaction with Oxazepam. Combining these substances can cause profound CNS and respiratory depression. This is considered a "do not use together" interaction — if your prescriber recommends Xyrem for narcolepsy or another condition, they must be informed you are taking Oxazepam.

Other CNS Depressants: Use With Caution

Any medication or substance that has sedating or depressant effects can enhance the sedation from Oxazepam. The following should only be combined with Oxazepam under explicit medical supervision:

• Other benzodiazepines: Additive sedation and dependence risk — avoid taking multiple benzodiazepines simultaneously
• Sleep medications (z-drugs): Zolpidem (Ambien), eszopiclone (Lunesta), and zaleplon (Sonata) all increase sedation
• Antipsychotics: Many antipsychotic medications (quetiapine, haloperidol, olanzapine) are sedating and can compound Oxazepam's effects
• Antihistamines: Over-the-counter sleep aids and allergy medications (diphenhydramine/Benadryl, doxylamine) significantly increase sedation
• Muscle relaxants: Cyclobenzaprine, methocarbamol, and similar medications are sedating and may interact
• Antiepileptics: Valproic acid, gabapentin, and other seizure medications can potentiate Oxazepam's sedating effects
• Certain anesthetics: Tell your anesthesiologist about Oxazepam before any surgical procedure

Why Oxazepam Has Fewer Drug Interactions Than Most Benzodiazepines

One advantage of Oxazepam is that it is metabolized via glucuronidation, not the CYP450 enzyme system. This means it avoids many of the pharmacokinetic drug interactions that affect other benzodiazepines. For example, the antibiotic ketoconazole or the SSRI fluvoxamine — drugs that inhibit CYP3A4 — can dramatically increase blood levels of other benzodiazepines like alprazolam or clonazepam. Oxazepam is largely unaffected by these CYP450 inhibitors, making it a better choice for patients on complex medication regimens.

What to Tell Every Provider You See

Always disclose your Oxazepam prescription to:

• Every doctor, including dentists and urgent care providers
• Your anesthesiologist before any procedure
• Your pharmacist — who can screen your entire medication list for interactions
• Any telehealth provider who might prescribe you a new medication

For a complete overview of Oxazepam side effects beyond interactions, see our article on Oxazepam Side Effects. And if you're having trouble finding Oxazepam at a pharmacy near you, medfinder.com can help you locate it.