How Long Does Restoril (Temazepam) Stay in Your System?

Restoril (temazepam) is in a class of drugs called benzodiazepines, which are central-nervous-system depressants and controlled substances. Restoril is typically prescribed as a short-term sleeping aid to treat insomnia for no more than 10 days and it works by slowing activity in your brain. When it's combined with other depressants or alcohol or taken in large dosages, Restoril can cause a loss of consciousness and respiratory failure, so it's important to know how long it remains in your system to avoid negative drug interactions.

Half-Life

The amount of time a benzodiazepine remains in your system depends partly on what type it is—ultra-short, short, intermediate, or long-acting. Ultra-short benzos have a half-life of fewer than five hours, while short- to intermediate-acting benzodiazepines have a half-life from five to 24 hours. Long-acting benzos have a half-life exceeding 24 hours. A half-life means that half the drug has been eliminated from your system and it takes five to seven half-lives to clear out 98 percent of a drug dose.

Restoril is classified as a short- to intermediate-acting benzodiazepine. It begins to work in 10 to 20 minutes after you take a dose, with the levels peaking at about one and a half hours later. It's then metabolized by your liver with a half-life in two phases, one short and one long, and most of it is secreted in your urine. The average half-life of Restoril is right around 9 hours.

How Long Restoril Stays in Your System

How long Restoril is detectable in your body depends on many other variables, including which kind of drug test is being used, your metabolism, weight, amount of body fat, hydration, how long you've been taking Restoril, and the amount of the drug that you have taken.

In general, the typical detection windows for benzodiazepines are:

  • Urine: A typical therapeutic dose of Restoril will appear positive on a urine drug screen, such as those done for employment purposes, for five days to a week, while heavier or longer use may create a positive test for up to 6 weeks.
  • Blood: Restoril clears out of your bloodstream much faster and is usually detectable for up to 24 hours.
  • Saliva: Restoril may be detectable in your saliva for 24 hours or more.
  • Hair: As with all drugs, Restoril can be found in your hair for up to three months.

If you have a drug test, be sure to tell the testing laboratory about all prescriptions you're taking so they can interpret your test appropriately.

Common Side Effects

It's recommended that you only take Restoril if you are able to stay in bed for seven to eight hours before you have to get up again as the medication will be sedating you during that time period.

The side effects most often noted from Restoril include:

  • Feeling groggy the next day
  • Drowsiness
  • Headache
  • Dizziness
  • Nervousness
  • Nausea
  • Lethargy
  • Anxiety
  • Depression
  • Dry mouth
  • Diarrhea

Though it's uncommon, you may also have instances of sleepwalking, which can include activities such as driving, cooking, talking on the phone, and having sex, but you have no memory of doing them.

If you have side effects and they don't go away or they're severe, be sure to tell your doctor.

Interaction With Other Drugs

Avoid drinking alcohol or using street drugs while taking Restoril as these increase your risk of developing life-threatening breathing problems, sedation, coma, or death. Other medications you shouldn't take with Restoril are those with any opiates, including codeine, hydrocodone, fentanyl, hydromorphone, Demerol, methadone, morphine, oxycodone, or tramadol, as these can also lead to breathing problems, sedation, coma, or death.

Other drugs that can potentially cause negative interactions with Restoril include:

  • Antidepressants
  • Antihistamines like Benadryl (diphenhydramine)
  • Digoxin
  • Anxiety medications
  • Medications for mental illness like antidepressants or antipsychotics
  • Antiepileptics (for seizures)
  • Medications to treat pain
  • Sedatives
  • Other sleeping pills
  • Tranquilizers

Discuss all of your medications, whether prescription or over-the-counter, including supplements and vitamins, with your doctor so they can be adjusted to avoid serious drug interactions.

Serious Side Effects

Call your doctor immediately if you experience any of these serious side effects:

  • Rash
  • Hives
  • Swelling of your face
  • Hoarseness
  • Difficulty breathing or swallowing

Overdose Signs

Signs of an overdose include:

  • Confusion
  • Dizziness
  • Drowsiness
  • Loss of consciousness
  • Difficulty breathing

If you think someone has overdosed on Restoril, call poison control at 1-800-222-1222. Get emergency help if the person has a seizure, loses consciousness, or has difficulty breathing.

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Article Sources
  • Mayo Medical Laboratories. Benzodiazepines. Mayo Foundation for Medical Education and Research. Mayo Clinic. http://www.mayomedicallaboratories.com/test-info/drug-book/benzodiazepines.html

  • U.S. Food and Drug Administration (FDA). Medication Guide: Restoril. Updated September 2016. http://www.accessdata.fda.gov/drugsatfda_docs/label/2016/018163s064lbl.pdf

  • MedlinePlus. Temazepam. The American Society of Health-System Pharmacists, Inc. National Institutes of Health. U.S. National Library of Medicine. Updated July 30, 2018. https://medlineplus.gov/druginfo/meds/a684003.html.

  • American Association for Clinical Chemistry. Drug Abuse Testing. Lab Tests Online. Updated March 15, 2018. https://labtestsonline.org/tests/drug-abuse-testing