Will Strattera (atomoxetine) and Vyvanse (lisdexamfetamine) show up on standard amphetamine or methamphetamine tests in a patient with a history of substance use and potential Attention Deficit Hyperactivity Disorder (ADHD) diagnosis?

Drug Testing for Strattera and Vyvanse in Patients with Substance Use History

Vyvanse (lisdexamfetamine) will test positive for amphetamines on standard drug screens because it is a prodrug that converts to d-amphetamine, while Strattera (atomoxetine) should not trigger amphetamine tests under normal circumstances, though rare false-positives have been reported. 1, 2

Vyvanse (Lisdexamfetamine) Testing Characteristics

Vyvanse will definitively show up as amphetamine-positive on urine drug screens. This is not a false positive—it represents the expected pharmacological conversion of the medication. 1

• Lisdexamfetamine is a prodrug of d-amphetamine (dextroamphetamine), meaning it is enzymatically converted to active amphetamine in the body 1
• The FDA label explicitly states that lisdexamfetamine contains amphetamine as a Schedule II controlled substance 1
• Standard immunoassay drug screens will detect the d-amphetamine metabolite, producing a positive result for amphetamines 1
• Gas chromatography-mass spectrometry (GC-MS) confirmation testing will verify the presence of d-amphetamine, confirming legitimate medication use 3

Strattera (Atomoxetine) Testing Characteristics

Atomoxetine typically does not cause positive amphetamine results, but one documented case report exists of a false-positive. 2, 4

• Atomoxetine is a selective norepinephrine reuptake inhibitor, not a stimulant, and is not chemically related to amphetamines 4, 5, 6
• Atomoxetine is not a controlled substance and has negligible abuse potential 4, 6
• One case report documented a false-positive amphetamine result on CEDIA immunoassay that could not be confirmed by GC-MS, implicating atomoxetine or its metabolites as potential interferents 2
• This false-positive phenomenon appears extremely rare and would not be confirmed by GC-MS testing 2

Critical Interpretation Guidelines for Clinicians

The American Academy of Pediatrics emphasizes that drug testing cannot distinguish between appropriate medication use and misuse—complete medical history is essential for accurate interpretation. 7

• A patient taking prescribed amphetamine-based medications (like Vyvanse) will have positive amphetamine results, which may be falsely interpreted as substance abuse without proper context 7
• To interpret results accurately, clinicians must know the patient's complete medication list, including all prescribed ADHD medications 7
• The American Academy of Pediatrics recommends direct observation as the most reliable specimen collection method to ensure accuracy 7
• Temperature should be recorded within 4 minutes of collection (90°F to 100°F or 32°-38°C) 7

Special Monitoring Considerations for Substance Use History

Patients with substance use history require more careful monitoring when prescribed stimulants, but this is not a contraindication to treatment. 7, 8

• The American Academy of Child and Adolescent Psychiatry recommends obtaining urine drug screens in adults with ADHD due to high rates of comorbid substance abuse 7
• For adolescents with newly diagnosed ADHD, the American Academy of Pediatrics recommends drug testing to assess for substance abuse symptoms 7
• When substance use is identified, assessment off the abusive substances should precede ADHD treatment 7
• Consider medications with lower abuse potential such as lisdexamfetamine (ironically, despite testing positive), atomoxetine, or long-acting methylphenidate formulations 7

Confirmation Testing Protocol

When positive amphetamine results occur, GC-MS confirmation testing distinguishes prescribed medication from illicit use. 3, 2

• Initial immunoassay screening may produce false-positives from various substances 3
• GC-MS confirmation can identify specific amphetamine compounds and distinguish d-amphetamine (from Vyvanse) from methamphetamine or illicit amphetamines 3, 2
• For legal matters, specimens require tamper-proof containers with chain of custody documentation 7
• The American Academy of Pediatrics notes that substituted or adulterated specimens should be considered "positive" and may indicate serious substance use disorder requiring specialist referral 3

Common Pitfalls to Avoid

• Do not assume a positive amphetamine test indicates illicit use without reviewing the patient's prescribed medications—Vyvanse will always test positive 7
• Do not rely solely on drug testing to diagnose substance use disorders; testing should supplement clinical history and examination 3
• Do not dismiss ADHD symptoms based solely on negative drug test results or inability to obtain testing—symptoms always require further evaluation 3
• Do not assume atomoxetine is completely immune from causing false-positive amphetamine results, though this is extremely rare and would not be GC-MS confirmed 2