OverviewDosageSide EffectsInteractionsHalf-Life

Amitriptyline was the 87th most commonly prescribed drug in the United States in 2017. In that year alone, there were over 9,105,080 prescriptions. Considering how popular this drug is right now, it pays to know a little bit more about this medication, including how long amitriptyline stays in your system.

Research studies show the following information regarding amitriptyline half-life:

Mean effective half-life: about 17 to 40 hours

Time to steady-state: about 3 to 8 days

Amitriptyline is absorbed and metabolized at a rapid rate. This medication appears in urine within 4 to 6 hours.


What is the half-life of amitriptyline?

The half-life of amitriptyline is roughly 17 to 40 hours, with the average being around 20 hours. For example, an individual will have roughly 10 milligrams of this drug in their system after a period of 20 hours if they take a 20 milligram dosage.

How long does amitriptyline stay in your system?

Research shows that between 1/2 to 1/3 of this medication is excreted within 24 hours of taking it. This medication is excreted in the form of metabolites, and other metabolic pathways might exist, although more research is needed to determine this. When amitriptyline appears in urine, it remains largely unchanged.

Individuals should be aware that different factors affect how long this drug remains in their system, such as the amount they take, genetic factors, their physical size, and whether they are taking other medications.

Amitriptyline may show up in drug tests, although the exact time that this is no longer the case varies from person to person. Exact lengths of time that this drug shows up on drug tests is not available, but individuals should keep in mind that detection windows also vary for the following tests:

  • Urine tests: Detection windows might be as short as several hours or up to a month.
  • Blood, serum, or plasma tests: Detection windows are generally shorter for these types of drug tests, ranging from a few hours to a few days.
  • Hair tests: Detection windows for these drug tests are typically longer and can reach up to 90 days in some cases.

How long does amitriptyline take to wear off?

The length of time it takes for amitriptyline to wear off varies for each individual based on different factors, such as how much they are taking. This medication generally has a half-life ranging from 17 to 40 hours depending on dosage and is readily absorbed.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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