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How Long Does Xanax Stay in Your System

Determining how long does Xanax stay in your system is calculated by its half-life. This amount of time is relative to other factors (see below) including how long someone has been taking it and in what dosages.


Here are some of the variables affecting elimination time;

  • Older adults cannot excrete the drug as fast because of the altered blood flow and the deterioration of internal organs’ function due to aging.
  • Individuals with impaired kidney or liver functions retain the drug for a more extended period.
  • Studies have shown that people of Asian descent have higher peak levels, and the effects last longer.
  • Obese people and alcoholics take longer to clear the drug and have a longer duration of action. The reason is that obese people have trouble breaking it down.

Calculate By Half-Life

It is essential to know the half-life for testing purposes. On average, the half-life range is 6-26 hours for a healthy person. On average, it is 11 hours. That means half of its amount is eliminated during this period, leaving behind 50% of the drug.

  • It will take several days, if not more, for this medication to entirely leave the body.

According to the FDA, the average half-life is 11.2 hours. Using that as the half-life, then the following is estimated for a 1mg dose:

  • 11.2 hours after administration, there is half-cleared to 0.5mg
  • 22.4 hours minutes after dosing, there is still 0.25mg
  • 33.6 hours after administration, there remains 0.125mg 
  • 44.8 hours after taking it, only this amount remains 0.063mg
  • Fifty-six hours after the dose, this volume is detectable 0.0315mg

Therefore, in theory, after 56 hours (2.3 days), almost all the initial doses (slightly less than 97%) remain in the body.

Other Drugs Effect Elimination

Whether prescription or illicit, taking other drugs and alcohol alters the body’s rate of effectively metabolizing this drug. These drugs can either be inhibitors or inducers of the enzymatic function of the CYP3A4, which is in the liver. Inhibitor drugs inhibit this enzymatic function and prolong the excretion of the drug.

The following medicines have moderate to significant interactions;

  • Ambien
  • Cymbalta
  • Flexeril
  • Gabapentin
  • Lexapro
  • lisinopril
  • Norco
  • Omeprazole
  • Oxycodone
  • Prozac
  • Tramadol
  • Trazodone

How It Works

Xanax (Alprazolam) is a benzodiazepine. It works by enhancing certain neurotransmitters in the brain to make the user calmer. The neurotransmitter is called GABA (gamma-aminobutyric acid) and depresses the central nervous system or calms the nerves. Benzodiazepines are also known for their amnesic effect, disrupting short-term memory, making them useful before surgery.

  • Its effects last approximately 5 hours with a relatively quick onset of action within one hour.

It is a fast-acting benzodiazepine, and the effects set in almost immediately after ingestion and peak 1 to 2 hours after ingestion. However, its impact wears off quickly, and the user needs to take more to continue feeling the effects.

Doctors prescribe it primarily for:

  • Anxiety
  • Seizures
  • Muscle spasms
  • Sleep disorders

According to research, 16 million Americans aged 12 and above have used it for recreational purposes at least once. It is the most prescribed and misused benzodiazepine in the US due to its propensity to cause addiction. Due to the USA’s high abuse rates, there are tests to detect the drug’s body fluids and tissue.


After 2 or 3 weeks, the user starts experiencing physical dependence and tolerance. In addition, it can be very addictive. Finally, withdrawal can be excruciating and should only be under the direction of a healthcare professional.

  • It can take approximately four days for a moderate dose to be removed entirely from the system for the average person.


Determining how long Xanax stays detectable in your system is based on these nine variables. These are the factors affecting detection time;

  1. Amount of it consumed
  2. Food intake during that period
  3. Age
  4. Weight
  5. Gender
  6. General health
  7. Genetics
  8. Liver health
  9. Length of time between doses
  10. Other medications
  11. Ethnicity
  12. Smoking
  13. Alcohol

Generally speaking, dosages are between 0.25 mg to 4 mg. Doctors try and prescribe the minimum effective dosage to their patients.

Individuals taking smaller dosages will metabolize and excrete the drug from their system faster than those taking a dosage higher.

Side Effects

Side effects can include:

  • Ataxia
  • Cognitive dysfunction
  • Constipation
  • Difficulty in urination
  • Drowsiness
  • Difficulty speaking clearly
  • Memory impairment
  • Skin rash
  • Weight gain or loss
  • Blurred vision
  • Diarrhea
  • Decreased libido
  • Increased or decreased appetite

What is blue Xanax?