Are Drug Tests Able To Detect Methamphetamine And Amphetamine?

In our latest question and answer, the pharmacist discusses whether or not a urine drug test can distinguish between methamphetamine and amphetamine.


Will a drug test show just as an amphetamine, not methamphetamine?

Asked by jam On Jul 02, 2018

Answered by
Medical Content Reviewed By PharmacistAnswers Staff

On Jul 02, 2018

Most commonly utilized urine drug tests can distinguish between amphetamine and methamphetamine. According to the Urine Drug Screening: Practical Guide for Clinicians from Mayo Clinic Proceedings:

Most amphetamine assays are designed to detect amphetamine, racemic compounds (eg, dextroamphetamine, methamphetamine), and illicit analogues (methylenedioxyethylamphetamine, methylenedioxyamphetamine, and methylenedioxymethylamphetamine [MDMA])

It is important to note that if you test positive for methamphetamine, amphetamine will be detected as well since it is an active metabolite of methamphetamine metabolism.

In most cases, methamphetamine is detectable in the urine for up to 48 hours since last use.

Methamphetamine False Positives

Urine drug screenings are subject to false positives and there are various substances that have been reported to cause a false-positive for methamphetamine. They include:

  • Amantadine
  • Brompheniramine
  • Bupropion
  • Chlorpromazine
  • Chloroquine
  • Desipramine
  • Doxepin
  • Labetalol
  • Methylphenidate
  • Phenylephrine
  • Promethazine
  • Pseudoephedrine
  • Ranitidine
  • Selegiline
  • Thioridazine
  • Trazodone
  • Trimethobenzamide
  • Venlafaxine
  • Vicks inhaler (l-methamphetamine)

Using an over the counter nasal inhaler that contains l-methamphetamine (also known as levomethamphetamine or levmetamfetamine) is likely to cause a false positive if you use it consistently. L-methamphetamine is essentially one-half of the methamphetamine molecule (the other being d-methamphetamine) and has very mild, if any, stimulant effect. Nevertheless, most urine drug tests are unable to differentiate between methamphetamine, d-methamphetamine and l-methamphetamine.

About the Pharmacist

Dr. Brian Staiger Pharm.D

Dr. Brian Staiger is a licensed pharmacist in New York State and the founder of He graduated from the University At Buffalo with a Doctor of Pharmacy degree in 2010. He has been featured in numerous publications including the Huffington Post as well as a variety of health and pharmacy-related blogs. Please feel free to reach out to him directly if you have any inquiries or want to connect! He's answered thousands of medication and pharmacy-related questions and he's ready to answer yours! Office: 716-389-3076

About Methamphetamine

Methamphetamine is a central nervous system stimulant, FDA-approved for attention-deficit hyperactivity disorder (ADHD) and for short-term, adjunctive treatment of obesity. Methamphetamine can be given with or without food, but if taking for the treatment of obesity, it should be given 30 minutes before food to increase the feeling a satiety. Avoid administration during the late evening due to the risk of insomnia. After taking a dose by mouth, maximum concentrations are achieved in 1.5-2 hours, with a duration of action around 4-8 hours. Methamphetamine is a schedule II controlled substance, with a high potential for abuse and addiction.

Recent Questions