Oxazepam (Serax)

Dr. Jenni Jacobsen, PhD
Author: Dr. Jenni Jacobsen, PhD Medical Reviewer: Amy Shelby Last updated:

Oxazepam is a benzodiazepine drug used in the treatment of anxiety disorders and symptoms of alcohol withdrawal. Some doctors may prescribe it for other uses, but it is important to know the risks and benefits of oxazepam, as it is classified as a controlled substance and can lead to respiratory depression and overdose if misused.[1]

Oxazepam brand names

The most common brand name for oxazepam is Serax.[2] It may also be found under brand names, including Serepax and Placidox.

What is oxazepam prescribed for?

Oxazepam is most commonly prescribed to treat symptoms of anxiety disorders and alcohol withdrawal symptoms [1] but doctors may also prescribe it for the following conditions: [1]

How does oxazepam work?

Oxazepam works as an anxiety-reducing medication because it belongs to a class of drugs called benzodiazepines. This type of drug influences the action of a neurotransmitter called GABA, which has inhibitory effects on the nervous system. This means that benzodiazepines slow nervous system activity, thus inducing a sedative or anxiety-reducing effect.[1]

How is oxazepam usually taken?

Oxazepam is typically taken orally. It is available in a 10 mg, 15 mg, or 30 mg capsule, or as a 15 mg tablet. [1]

For mild to moderate anxiety, patients typically take 10-15 mg every 6-8 hours, with a maximum dosage of 120 mg per day. For severe and ongoing anxiety, a patient may take 15-30 mg every 6 to 8 hours [1].

For alcohol withdrawal, a typical dose is 15 mg, taken three times per day. Dosages for older adults generally should not exceed 60 mg per day, and doses for children vary based on body weight. Children under 6 years of age should not take this medication. [1]

A doctor prescribing oxazepam will give instructions for how often the medication should be taken, and how large of a dose you should take. It is generally recommended that doctors prescribe the lowest effective dose for the shortest amount of time possible. [1]

How long does oxazepam stay in your system?

Oxazepam is a short-acting benzodiazepine, meaning its effects occur relatively quickly when compared to other benzodiazepines. It has a half-life ranging from three to 21 hours, meaning that half of the initial dose is eliminated from the body within this time frame.[1]

Research with oxazepam has shown that it can be detected in the urine for an average of 91 hours, or a little under four days. It is detectable in saliva for an average of 67 hours or just under three days.[3]

Oxazepam side effects

Oxazepam is a prescription medication with legitimate medical uses, but it does come with side effects. If your doctor prescribes this medication, it is because he or she has determined that the benefits of the medication outweigh the risks for you.

The following are the most common side effects associated with oxazepam: [1]

  • Extreme sedation
  • Severe drowsiness
  • Blurred vision
  • Feelings of fatigue
  • Confusion
  • Memory problems
  • Dizziness
  • Depressed mood
  • Lack of coordination
  • Slurred speech
  • Nervousness or over-excitability
  • Weakness

Some of the side effects of oxazepam can be more severe. The following are rare but potentially serious adverse effects from oxazepam: [1]

  • Low blood pressure
  • Hallucinations
  • Manic behavior
  • Dry mouth
  • Excessive salivation
  • Edema
  • Upper stomach pain
  • Reduced sex drive
  • Low white blood cell count
  • Incontinence
  • Rash
  • Irregular menstrual cycles
  • Jaundice
  • Amnesia
  • Respiratory depression (difficult breathing)

Oxazepam precautions

Before taking oxazepam, it is important to tell your doctor about other medications you’re taking or any existing health conditions. Some medications you are taking may have potentially dangerous side effects when combined with oxazepam.

Beyond the potential for interaction effects with other medications, oxazepam can be habit-forming or addictive. This means that you should never take larger doses of this medication than prescribed, nor should you take it for reasons aside from its intended medical uses.[4]

You may become dependent on oxazepam with long-term use, even if you take it exactly as prescribed. This means that if you abruptly stop taking your medication, you may experience withdrawal side effects. Doctors generally advise patients to gradually reduce their dose of oxazepam, rather than abruptly discontinuing the medication. Do not stop taking oxazepam without speaking with your doctor first.[4]

Oxazepam interactions

As noted above, oxazepam may cause dangerous interactions when combined with other medications. Some of the medications that should not be used with oxazepam, due to the potential for negative interactions, are described below.

CNS Depressants

Oxazepam has a depressant effect on the central nervous system (CNS) and should not be used with other medications that act as CNS depressants. One medication in this category is the antihistamine drug diphenhydramine. When used in combination with other CNS depressants, oxazepam can cause an increased risk of respiratory depression. [1]

Opioid Drugs

Opioid medications like methadone, hydrocodone, and morphine can cause severe sedation, low blood pressure, and respiratory depression when taken concurrently with oxazepam. [1]

Other Medications

In addition to the medications noted above, the drugs on the following list may also cause interaction effects with oxazepam. Tell your doctor if you are taking any of the medications below, as you may need to be closely monitored for interaction effects: [4]

  • Digoxin
  • Levodopa
  • Depression medications
  • Anti-seizure medications
  • Medications for Parkinson’s disease
  • Sedatives
  • Sleeping pills
  • Asthma, cold, or allergy medications
  • Oral contraceptives
  • Probenecid
  • Rifampin
  • Theophylline

The list above is not exhaustive. Talk with your doctor if you have questions about what medications you can and cannot take with oxazepam.

Oxazepam storage

To maintain the functionality of your medication, you should keep oxazepam stored in a room temperature setting without any exposure to moisture or excessive heat. For example, the bathroom is not ideal for storing this medication. [4]

You should also keep oxazepam in its original, tightly sealed prescription container to prevent anyone from accidentally taking your medication. Oxazepam should be kept out of reach of children and should be disposed of in a manner that does not allow children to access this medication.[4]

What to do if you overdose on oxazepam

If you’re taking oxazepam, it’s important to be aware of the risk of overdose. Accidental injury or verdose risk is higher when the medication is misused, taken in large doses, or combined with other CNS depressants. The following symptoms are indicative of an oxazepam overdose: [2]

  • Extreme drowsiness
  • Confusion
  • Lethargy
  • Severely low blood pressure
  • Appearing to be in a hypnotic state
  • Muscle weakness
  • Coma
  • Breathing problems

If you think you or someone you love is experiencing an oxazepam overdose, it’s important to call 911 or report immediately to the nearest emergency department. An oxazepam overdose can be fatal and requires immediate medical treatment.[4]

Someone who collapses, experiences trouble breathing, or is unable to be awakened is in especially critical condition and should receive immediate medical attention.[4]

Frequently asked questions about oxazepam

If you’re searching for information on oxazepam, the answers to the following common questions are also helpful.

Is Oxazepam addictive?

Medications in the benzodiazepine class, including oxazepam, are potentially addictive. Even when taken as prescribed by a doctor, these medications can result in physical dependence, meaning that the body does not function the same without them and will experience withdrawal side effects when the medication is stopped. Common withdrawal side effects associated with oxazepam include convulsions, tremors, stomach pain, muscle cramps, vomiting, sweating, insomnia, and unhappy mood.[2]

Given the risk of physical dependence and withdrawal that comes with oxazepam use, it is generally recommended that patients slowly taper off of this medication, rather than abruptly cease taking it.[2] In addition, doctors are often advised against prescribing oxazepam to individuals with a history of substance misuse, given the risk of addiction to this medication.[1]

What’s the difference between Oxazepam and Diazepam?

Oxazepam and diazepam both belong to the benzodiazepine class of drugs, meaning they have similar uses and effects. Diazepam is a bit faster acting when compared to oxazepam. The onset of action for diazepam is generally less than or equal to 15 minutes, whereas the onset of action for oxazepam is usually 30-60 minutes.[5]

Research suggests that diazepam is more likely to produce the sensation of being “high” when compared to oxazepam. Therefore, people may be more likely to misuse or develop an addiction to diazepam when compared to oxazepam.[5]

  1. Singh, R., & Abdijadid, S. (2022). Oxazepam. National Library of Medicine. Accessed October 31, 2022, from https://www.ncbi.nlm.nih.gov/books/NBK544349/
  2. Food and Drug Administration. (2000). Serax. Retrieved October 31, 2022, from https://www.accessdata.fda.gov/drugsatfda_docs/label/2001/15539s52lbl.pdf
  3. Brunn, L.D., Kjeldstadli, K., Temte, V., Birdal, M., Bachs, L., Langodegard, M., Strand, D.H., Gaare, K.I., Oiestad, E., Hoiseth, G. (2019). Detection time of oxazepam and zopiclone in urine and oral fluid after experimental oral dosing. Journal of Analytical Toxicology, 43(5), 369-377. https://doi.org/10.1093/jat/bky083
  4. MedlinePlus. (2021). Oxazepam. National Library of Medicine. Retrieved October 31, 2022, from https://medlineplus.gov/druginfo/meds/a682050.html
  5. Schmitz, A. (2016). Benzodiazepine use, misuse, and abuse: A review. Mental Health Clinician, 6(3), 120-126. https://doi.org/10.9740/mhc.2016.05.120
Medical Content

Our Medical Affairs Team is a dedicated group of medical professionals with diverse and extensive clinical experience who actively contribute to the development of our content, products, and services. They meticulously evaluate and review all medical content before publication to ensure it is medically accurate and aligned with current discussions and research developments in mental health. For more information, visit our Editorial Policy.

About MentalHealth.com

MentalHealth.com is a health technology company guiding people towards self-understanding and connection. The platform offers reliable resources, accessible services, and nurturing communities. Its mission involves educating, supporting, and empowering people in their pursuit of well-being.

Dr. Jenni Jacobsen, PhD
Author Dr. Jenni Jacobsen, PhD Medical Reviewer, Writer

Dr. Jenni Jacobsen, PhD is a medical reviewer, licensed social worker, and behavioral health consultant, holding a PhD in clinical psychology.

Published: Nov 22nd 2022, Last edited: Oct 24th 2023

Amy Shelby
Medical Reviewer Amy Shelby M.S. Counseling Psychology

Amy Shelby is a medical reviewer with a B.A. in Psychology from Northwestern and an M.S. in Psychology from Chatham University.

Content reviewed by a medical professional. Last reviewed: Nov 23rd 2022