Drug & supplement interaction

1,3-dmaa + Phentermine

Phentermine brand names: Adipex-P, Fastin, T Diet, Phentride, Obenix, and others.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

1,3-dmaa has a moderate interaction with Phentermine. 1,3-DMAA is thought to have stimulant effects.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

1,3-dmaa and Phentermine

Here is the interaction we found between these two, with the evidence behind it.

Moderate

STIMULANT DRUGS

Why this applies to Phentermine

Phentermine falls under STIMULANT DRUGS — the group 1,3-dmaa interacts with.

1,3-DMAA is thought to have stimulant effects. There is concern that taking 1,3-DMAA with stimulant drugs might increase the risk of adverse cardiovascular effects. Some preliminary research shows that taking 1,3-DMAA 50 mg daily in combination with caffeine 250 mg daily does not increase respiratory rate, blood pressure, or other cardiovascular outcomes compared to taking caffeine alone in healthy men. However, a number of cardiovascular side effects have been reported for patients taking 1,3-DMAA in combination with other stimulants including caffeine. Theoretically, combining 1,3-DMAA with stimulant drugs might increase the risk of adverse cardiovascular effects. Some stimulant drugs include amphetamine, caffeine, diethylpropion (Tenuate), methylphenidate, phentermine (Ionamin), pseudoephedrine (Sudafed, others), and many others.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: phentermine is itself a stimulant that revs up your fight or flight system, raising your heart rate and blood pressure to dull your appetite. DMAA does much the same thing. So you're not changing how phentermine is broken down here, you're stacking two stimulants on top of each other, and the effects can add up.

Together, that could mean a racing or pounding heart, a real jump in blood pressure, jitteriness, headaches, chest discomfort, or trouble sleeping. In serious cases, stimulant pile-ups have been tied to dangerous heart and blood vessel events. This concern is mostly theoretical, based on how the two work rather than strong studies, but DMAA is also banned by the FDA as unsafe. Please don't combine them without talking to your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Adverse Event Report. Jack3d. Natural MedWatch, May 28, 2011.
  2. Smith TB, Staub BA, Natarajan GM, et al. Acute myocardial infarction associated with dietary supplements containing 1,3-dimethylamylamine and Citrus aurantium. Tex Heart Inst J 2014;41(1):70-2. PubMed
  3. Armstrong M. Atrial Fibrillation with Rapid Ventricular Response following use of Dietary Supplement Containing 1,3 Dimethylamylamine and Caffeine. J Spec Oper Med. 2012 Winter;12(4):1-4. PubMed
  4. Bloomer RJ, Farney TM, Harvey IC, Alleman RJ. Safety profile of caffeine and 1,3-dimethylamylamine supplementation in healthy men. Hum Exp Toxicol. 2013 Nov;32(11):1126-36. PubMed
  5. Brown JA, Buckley NA. Toxicity from bodybuilding supplements and recreational use of products containing 1,3-dimethylamylamine. Med J Aust. 2013 May 6;198(8):414-5. PubMed
  6. Dolan SB, Gatch MB. Abuse liability of the dietary supplement dimethylamylamine. Drug Alcohol Depend. 2015 Jan 1;146:97-102. PubMed
  7. Forrester M. Exposures to 1,3-dimethylamylamine-containing products reported to Texas poison centers. Hum Exp Toxicol. 2013 Jan;32(1):18-23. PubMed
  8. Van Hout MC, Hearne E. "Plant or poison": A netnographic study of recreational use of 1,3-dimethylamylamine (DMAA). Int J Drug Policy. 2015 Dec;26(12):1279-81. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

1,3-dmaa Also Interacts With Other Medications

1,3-dmaa has 320 moderate known drug interactions in our database — the Phentermine one above is one of them. If you take anything else, check it against the full list below.

Moderate 320 No known interaction 2,510 (incl. Phentermine)
Taking anything else?

Check Another of Your Medications Against 1,3-dmaa

Covers the 2,830 medications we’ve checked against 1,3-dmaa. Pick one to open its full report.

From our Q&A

Questions About 1,3-dmaa or Phentermine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers 1,3-dmaa or Phentermine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Phentermine

This page covers 1,3-dmaa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phentermine page lists 61 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Peyote (major), Rauvolfia Vomitoria (major) and Sida Cordifolia (major).

By severity: 5 major · 43 moderate · 13 minor.

From our pharmacist’s overview on the Phentermine page

“Ephedra is the pairing I most want anyone taking phentermine (Adipex-P) to know about. Phentermine is itself a stimulant appetite suppressant that raises heart rate and blood pressure, and ephedra piles the same cardiovascular strain on top of it.”

Reviewed by 2 · Jul 18, 2026

Open the Phentermine interaction page

One more smart check

Taking 1,3-dmaa as Part of a Dietary Supplement Product? Check It for Interactions

We hold 94 real supplement products containing 1,3-dmaa, each one broken down to its full ingredient list — and combination products often carry several ingredients besides 1,3-dmaa. Your product may carry other ingredients that interact with Phentermine too, on top of 1,3-dmaa — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where 1,3-dmaa and Phentermine Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement 1,3-dmaa
Top half

#413 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phentermine
Top 25%

#330 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About 1,3-dmaa

What is 1,3-dmaa?

1,3-dmaa
  • Energy and stimulation
  • Pre-workout performance
  • Weight loss
  • Appetite suppression
  • Focus and concentration

DMAA (1,3-dimethylamylamine) is a synthetic stimulant that was sold in pre-workout and weight-loss supplements but has been linked to serious harm, including high blood pressure, heart problems, strokes, and deaths. The U.S. FDA and regulators in many countries have declared it illegal and unsafe in dietary supplements, so it should be avoided.

Read the full 1,3-dmaa monograph & all interactions
Medication

About Phentermine

What Is Phentermine Used For?

Brand names: Adipex-P, Fastin, T Diet, Phentride, Obenix, Pbc Phentride, Pbw Phentride, Phentrol #3, Ionamin, Phentrol #6, Phentrol #2, Phentrol #5, Phentrol, Obermine, Phentermine, Suprenza

Phentermine is approved as a short-term addition to a weight-loss program — not a standalone treatment. It is used alongside reduced-calorie eating, increased physical activity, and behavior changes to help manage obesity in adults whose body mass index (BMI) is 30 kg/m² or higher, or 27 kg/m² or higher when other risk factors such as controlled high blood pressure, diabetes, or high cholesterol (hyperlipidemia) are also present.

All available phentermine products — including Adipex-P, Lomaira, and various generic capsules and tablets — share this same FDA-approved use. Lomaira tablets are specifically dosed to be taken three times daily before meals, while other formulations are generally taken once daily. Treatment is intended to last only a few weeks.

See full Phentermine drug information
Keep checking

Other Drugs & 1,3-dmaa

Browse every other medication we’ve checked against 1,3-dmaa — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
320Moderate
0Minor
2,509No known interaction
320 Moderate 2,509 No interaction
Moderate

320 interactions

Showing 60 of 320 moderate interactions — see all 320 on the 1,3-dmaa page.

No interaction 2,509 drugs checked — show the list

We also checked 1,3-dmaa against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,509 medications checked with no known interaction — see the full 1,3-dmaa list.

See the full 1,3-dmaa interactions page
See every supplement checked against Phentermine, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
1,3-dmaa monograph › Uses, safety, and every drug interaction in one place Phentermine supplement interactions › Every supplement checked against Phentermine, ranked by severity Phentermine drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking 1,3-dmaa and Phentermine Together: Common Questions

Can you take 1,3-dmaa with Phentermine?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the 1,3-dmaa and Phentermine interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Phentermine and 1,3-dmaa?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.