Methamphetamine and Amitriptyline: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Amitriptyline
Methamphetamine
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
You've been prescribed two medicines that both raise serotonin, a chemical messenger in your brain. Amitriptyline (Elavil) is an antidepressant, and methamphetamine (Desoxyn) is a stimulant. When you take them together, the extra serotonin can sometimes build up too much and cause a rare but serious problem called serotonin syndrome.
Warning signs include agitation, a racing heart, sweating, shivering, muscle twitching, fever, or feeling confused. Together they can also push up your blood pressure and heart rate. The good news is your care team can manage this by starting low, watching you closely, and adjusting things. Keep taking both as prescribed and call your doctor or pharmacist if you feel off.
Effect: Additive serotonergic activity increases the theoretical risk of serotonin syndrome. Amitriptyline inhibits serotonin (and norepinephrine) reuptake; methamphetamine promotes monoamine release and blocks reuptake. Neither is a prodrug relevant to reversing this direction; effects are additive/pharmacodynamic.
- Direction: Increased serotonergic and sympathomimetic (cardiovascular) effects; possible sustained CNS d-amphetamine exposure.
- Onset: Unspecified; highest risk at initiation and dose changes.
- Evidence: Theoretical.
- Management: If coadministration is required, initiate at lower doses, monitor HR, BP, mental status, and neuromuscular signs. Discontinue both agents if serotonin syndrome is suspected.
What happens
An increased risk of serotonin syndrome
Interaction Deep Dive
When an amphetamine is given together with another serotonergic drug, serotonin syndrome can develop, since both agents act on the serotonergic neurotransmitter system12. There may also be prolonged elevations in brain d-amphetamine levels, along with the potential for enhanced cardiovascular effects1. Should combined therapy with an amphetamine and such an agent be clinically necessary, begin with reduced doses and observe patients closely, particularly when starting treatment and when adjusting the dose. If serotonin syndrome is suspected, stop both medications32.
Why it happens (mechanism)
Additive serotonergic effects
How to manage this interaction
Both of these medicines act on serotonin, so your care team pays extra attention when they are used together.
- Keep taking both exactly as prescribed unless your doctor tells you otherwise.
- Your team may start at lower doses and adjust and individualize your dose over time.
- Expect closer monitoring, especially when starting or changing a dose, including checks of your heart rate and blood pressure.
- Learn the warning signs of serotonin syndrome: agitation, confusion, fast heartbeat, sweating, shivering, muscle twitching, or fever.
- Seek care right away if these occur, and mention every medicine and supplement you take to your pharmacist or prescriber.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Methamphetamine and Amitriptyline together?
Taking amitriptyline with methamphetamine can add up serotonin and stimulant effects, raising the theoretical risk of serotonin syndrome and higher heart rate or blood pressure. Keep taking both as prescribed, watch for warning signs, and let your care team monitor and tailor your doses. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Methamphetamine and Amitriptyline interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Methamphetamine and Amitriptyline interaction managed?
Both of these medicines act on serotonin, so your care team pays extra attention when they are used together. Keep taking both exactly as prescribed unless your doctor tells you otherwise. Your team may start at lower doses and adjust and individualize your dose over time. Expect closer monitoring, especially when starting or changing a dose, including checks of your heart rate and blood pressure.… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Methamphetamine or Amitriptyline need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: VYVANSE(R) oral capsules, oral chewable tablets, lisdexamfetamine dimesylate oral capsules, oral chewable tablets. Shire US Inc (per DailyMed), Lexington, MA, 2018. DailyMed
- Product Information: FETZIMA(R) oral extended-release capsules, levomilnacipran oral extended-release capsules. AbbVie Inc (per FDA), North Chicago, IL, 2023. DailyMed
- Product Information: ADDERALL(R) oral tablets, dextroamphetamine saccharate amphetamine aspartate dextroamphetamine sulfate amphetamine sulfate oral tablets. Teva Select Brands (per FDA), Horsham, PA, 2017. DailyMed
Keep reading about Amitriptyline
Keep reading about Methamphetamine
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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