How Long Do Amphetamines Stay In Your System?

Amphetamines stay in your system for 24-48 hours. But heavy use can be detected up to 7 days after ingestion. More on how long amphetamines are in your body here.

minute read
Reviewed by: Dr. Dili Gonzalez, M.D.

ARTICLE OVERVIEW:  Half of the amount of amphetamine that you take is eliminated by your body in under 11 hours. But heavy and chronic amphetamine use can be detected in your system up to one week after your last dose. More on drug testing and metabolism here.


How Do You Take Amphetamines?

The most common forms of amphetamines are pills, tablets, or capsules, which are swallowed. The less frequent forms, liquid and powder, can be injected or snorted but using this routes of administration increases risk for addiction to amphetamines. This is because getting high on amphetamines increases your risk of mental dependence on them.

Main ways people take amphetamines include:

  • Oral via tablets or capsules
  • Intravenous injection
  • Smoking, and intranasal snorting

What Are Amphetamines Used For?

Amphetamine and methamphetamine are substances regulated under the Controlled Substances Act asSchedule II stimulants. Both drugs have been used for treating attention deficit disorder in children, obesity, and narcolepsy. Medically, amphetamines are mostly prescribed by doctors treating ADD and ADHD. But amphetamines have also been used as a weight loss medication or have been prescribed to treat depression in some rare cases.

Amphetamines are central nervous system stimulants that initially produce euphoria, a feeling of well-being, increased self-esteem, and appetite suppression followed by restlessness and irritability. A single therapeutic dose often enhances attention and performance, but exhaustion eventually occurs and performance deteriorates as the effects wear off.

Peak Levels and Half Life

The duration of a single dose effect of amphetamines lasts from 2 to 4 hours. Residual effects of amphetamines can last longer. Peak plasma concentrations of amphetamine occur approximately 3 hours post-dose for l-amphetamine. The amphetamine metabolite peaks at 12 hours.

The mean elimination half-life for d-amphetamine is between 9.77-11 hours. Following intravenous injection, however, the mean elimination half-life of the amphetamine metabolite is slightly longer at 12.2 hours.

Amphetamine Drug Testing

How long do amphetamines stay in the body? Detection periods for amphetamines vary. This is because rates of metabolism and excretion are different for each drug, each use and vary by individual.

For amphetamines, no metabolites are identified because these substances normally pass through the body essentially unchanged in chemical structure.  So, most amphetamine-specific drug tests are based on urine samples. Typical drug testing detection windows for amphetamines follow.

Blood Tests:Blood concentrations are generally used to distinguish therapeutic use from abuse.

Hair Tests:Amphetamines can be detected in hair for up to 90 days.Confirmation testing and cut-off levels for amphetamines, methamphetamine, MDA and MDMA in hair are 150-500 ng/mL.

Saliva Tests:In oral fluid, most stimulant drugs are typically detected for 12 to 48 hours, although methylamphetamine has been detected for 72 hour following multiple doses. Confirmatory target concentrations for detection of amphetamines in oral fluid are 25 ng/mL.

Urine Tests:In general, amphetamines (including methamphetamine) have a drug and detection period of 1-2 days in urine testing, although some sources claim to be able to detect amphetamines up to 4 days after you take them.This is because the drug stays in the body longer when urine is alkaline, allowing reabsorption and thus allowing more of it to be metabolized. In 24 hours, about 74% of a dose will be excreted unchanged if urine is acidic, while 1 to 2 % is excreted if urine is alkaline.

How Do Urine Tests Work?

Urine-based testing kits contain strips that come indifferent forms: as a dipstick, a dip card, a cassette test device, or a test cup. Usually, strips contain a membrane coated with different drug-protein conjugates, antibodies, or particles specific against the drug being tested. If the concentration of drug is below the cutoff level, the tests produce a band which indicate a negative result. If the drug concentration is at the cut off level or higher no band will form in the test zone indicating a preliminary positive.

Approximations are due to variables such as drug metabolism and half-life, person’s physical condition, fluid intake and method and frequency of use. This is why detection periods for amphetamines should be viewed as estimates. Cases can always be found to contradict these approximations.

False Positive Tests

Many “over-the-counter” (OTC) and prescription medicines contain chemicals that are structurally related to amphetamine. These compounds can be identified in the standard amphetamine screening procedures or mistaken for amphetamines. In fact, the Physicians’ Desk Reference provides a list of more than 350 medications that may produce positive test results for amphetamines.

If you are taking cough suppressants, antihistamines, antibiotics or other OTC or prescription medications, be sure to report these to drug testing staff. Positive test results for amphetamines can occur and you should be clear about what you are taking.

Testing for Amphetamines at Home

At home tests are fairly sensitive to the presence of most kinds of drugs in the urine. This means that if drugs are present, you will usually get a preliminary (or presumptive) positive test result. If you get a preliminary positive result, you should send the urine sample a drug testing laboratory for a second test.

Why do you need confirmation?

Certain foods, food supplements, beverages, or medicines can affect the results of at-home tests. Laboratory tests are the most reliable way to confirm drugs of abuse. Many other things can affect the accuracy of these types of self-administered tests, including (but not limited to):

  • Over-the-counter drugs in your system
  • Prescription drugs in your system
  • The way you did the test
  • The way you stored the test or urine
  • What you ate or drank before taking the test

Note that a result showing the presence of an amphetamine should be considered carefully, even when this result is confirmed in the laboratory testing. Some over-the-counter medications will produce the same test results as illegally-abused amphetamines.

Amphetamine Addiction Liability

Amphetamines can be very addictive. In fact, large doses and long term use of amphetamines can cause higher tolerance levels and dependence, which lead to addiction. Physical dependence on drugs like Adderall require detox and withdrawal periods (Adderall withdrawal how long?)

Although physical dependence on amphetamines is possible, psychological and mental dependence is more frequent and known to increase risk of amphetamine addiction. Frequent, repeated high-dose use of amphetamines produces:

  • Exhaustion
  • Lethargy
  • Mental confusion
  • Paranoid thoughts

So, how do you know if you have problems with amphetamines or not? Well, if you think that you have a problem…then you probably do. The main signs of an addiction are:

  1. Continued use despite negative consequences.
  2. Loss of control of use.
  3. Trying but failing to quit on your own.

Amphetamines provoke strong cravings. So, it’s really difficult to quit once you’re hooked. For more info on the addictive potential of amphetamines, what is the best addiction treatment program for you, and what you can expect during rehab…check out in our The A-Z GUIDE: Help for Amphetamines and Speed.

Get Help Now

Recovering from an amphetamine problem usually begins with a medical detox. The detox process helps prevent relapse and issues caused by withdrawal symptoms. It can help you address depression and fatigue…plus, medical detox keeps you safe when suicidal ideation occurs.

Rehabs provide detox as well as counseling to change behaviors that lead to the use of stimulants. If you’re struggling with any kind of amphetamine and are ready to quit, give us a call. We’ll connect you with a hotline operator who can talk you through your treatment options today.

Also, we’d like to hear from you! Please send us your questions, and we will help you find an answer. Feedback, comments, and experience is also welcomed in the comment section below.

Reference sources: SAMHSA/CSAT Treatment Improvement Protocols: Chapter 9, Drug Testing as a Tool
National highway Traffic Safety Administration fact sheet on methamphetamine (and amphetamine)
FDA: Drugs of Abuse Home Use Test
SAMHSA: Medical Review Officer Guidance Manual for Federal Workplace Drug Testing Programs
U.S. Department of Energy, Office of Health, Safety and Security, Office of Security Policy:Drug Retention Times
The Journal of Analytical Toxicology: Comparison of Urine and Oral Fluid for Workplace Drug Testing






About the author
Lee Weber is a published author, medical writer, and woman in long-term recovery from addiction. Her latest book, The Definitive Guide to Addiction Interventions is set to reach university bookstores in early 2019.
Medical Reviewers
Dr. Dili Gonzalez, M.D. is a general surgeon practicing women's focused medici...

All of the information on this page has been reviewed and verified by a licensed medical professional.

I am ready to call
i Who Answers?