Secretin + Phentermine
Phentermine brand names: Adipex-P, Fastin, T Diet, Phentride, Obenix, and others.
We found no known interaction between Secretin and Phentermine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.
Secretin and Phentermine
We checked these two against our interaction database. Here is what we found.
No Known Interaction Found
We did not find a documented interaction between Phentermine and Secretin in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.
Worth understanding: our licensed dataset holds no drug-interaction record for Secretin at all — not against Phentermine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.
If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.
Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.
Secretin safety at a glance
Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Questions About Secretin 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 Secretin 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:
- Can You Take Phentermine With Berberine? ›
- Interaction Question: Omeprazole, Spironolactone And Phentermine ›
- Lomaira With Pristiq - Interaction Details ›
Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.
See Every Supplement That Interacts With Phentermine
This page covers Secretin 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
Where Secretin 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.
#1,174 of 1,452 supplements looked up here in the last 7 days
#330 of 2,830 medications looked up here in the last 7 days
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.
Where does our data come from?
- Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
- Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Secretin reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Secretin and Phentermine records this page draws on were last updated July 10, 2026.
- What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
About Secretin
What is Secretin?
- Diagnostic testing of pancreas function
- Diagnosing gastrinoma (Zollinger-Ellison syndrome)
- Aiding pancreatic imaging procedures
- Investigational use in autism (not proven)
Secretin is a natural digestive hormone, not a typical dietary supplement. As a medicine it is an FDA-approved injectable used mainly for diagnostic tests of the pancreas, and it must be given by a healthcare professional. Despite past interest, there is strong evidence that secretin does NOT help autism, and it should never be self-administered.
Hormone produced naturally in the small intestine; pharmaceutical versions are made synthetically or from animal sources · Injectable solution (prescription, used in medical settings)
An interaction check asks whether these two react with each other — it does not ask whether Secretin is a good idea for someone in your situation. Here is what our Secretin record says about it on its own.
Secretin: dosing
There is no general supplement dose for secretin because it is not used as a supplement. It is a prescription injectable, and the dose is calculated by your healthcare provider based on your body and the specific test being done.You should never try to obtain or self-administer secretin. Dosing, timing, and monitoring are all handled by trained medical staff during a procedure.
From our Secretin monograph — the full record covers uses, side effects and every documented interaction.
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.
Other Drugs & Secretin
Browse every other medication we’ve checked against Secretin — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
No interaction 2,829 drugs checked — show the list
We also checked Secretin against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Warfarin ›
- Methylphenidate ›
- Sertraline ›
- Abemaciclib ›
- Ivermectin ›
- Testosterone ›
- Acetaminophen ›
- Losartan Potassium ›
- Aspirin ›
- Rosuvastatin ›
- Metoprolol ›
- Clopidogrel ›
- Escitalopram ›
- Rivaroxaban ›
- Atorvastatin ›
- Docusate ›
- Tirzepatide ›
- Ibuprofen ›
- Methamphetamine ›
- Warfarin Sodium ›
- Tadalafil ›
- Valacyclovir ›
- Hydroxyurea ›
- Sumatriptan ›
- Semaglutide ›
- Prednisone ›
- Amitriptyline ›
- Propranolol ›
- Metformin ›
- Lisdexamfetamine ›
- Isotretinoin ›
- Amoxicillin ›
- Methotrexate ›
- Lisinopril ›
- Amlodipine Besylate ›
- Amphetamine ›
- Bendamustine ›
- Bupropion ›
- Fluoxetine ›
- Doxycycline ›
- Azithromycin ›
- Pregabalin ›
- Acyclovir ›
- Lamotrigine ›
- Dextroamphetamine ›
- Gabapentin ›
- Levothyroxine, Liothyronine ›
- Acetaminophen, Codeine ›
- Naproxen ›
- Clonazepam ›
- Quetiapine ›
- Omeprazole ›
- Duloxetine ›
- Letrozole ›
- Methylene Blue ›
- Citalopram ›
- Buspirone ›
Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Secretin list.
Secretin References
The 14 references that drive our Secretin monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- Horvath K, Stefatos G, Sokolski KN. Improved social and language skills after secretin administration. J Assoc Acad Minor Phys 1998;9:9-15.
- Tympner F, Rosch W. The treatment of chronic recurrent pancreatitis with depot secretin-a preliminary report. Hepatogastroenterology 1986;33:159-62.
- Coniglio SJ, Lewis JD, Lang C, et al. A randomized, double-blind, placebo-controlled trial of single-dose intravenous secretin as treatment for children with autism. J Pediatr 2001;138:649-55. PubMed
- Secretin for the treatment of autism. Pharmacist's Letter/Prescriber's Letter 1998;14(12):141212.
- Sandler AD, Sutton KA, DeWeese J, et al. Lack of benefit of a single dose of synthetic human secretin in the treatment of autism and pervasive developmental disorder. N Engl J Med 1999;341(24):1801-6. PubMed
- Lightdale JR, Hayer C, Duer A, et al. Effects of intravenous secretin on language and behavior of children with autism and gastrointestinal symptoms: a single-blinded, open-label pilot study. Pediatrics 2001;108:90. PubMed
- Roberts W, Weaver L, Brian J, et al. Repeated doses of porcine secretin in the treatment of autism: A randomized, placebo-controlled trial. Pediatrics 2001;107:e71. PubMed
- Honomichl RD, Goodlin-Jones BL, Burnham MM, Hansen RL, Anders TF. Secretin and sleep in children with autism. Child Psychiatry Hum Dev. 2002;33(2):107-23. PubMed
- Law R, Vargo JJ, Stevens T. Acute pancreatitis and aspiration pneumonia after administration of synthetic human secretin (with video). Gastrointest Endosc. 2011;74(5):1166-8. PubMed
- Sheitman BB, Knable MB, Jarskog LF, et al. Secretin for refractory schizophrenia. Schizophr Res. 2004;66(2-3):177-81. PubMed
- Levenick JM, Andrews CL, Purich ED, Gordon SR, Gardner TB. A phase II trial of human secretin infusion for refractory type B pain in chronic pancreatitis. Pancreas. 2013;42(4):596-600. PubMed
- Williams K, Wray JA, Wheeler DM. Intravenous secretin for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2012;2012(4):CD003495. PubMed
- Brandler J, Miller LJ, Wang XJ, et al. Secretin effects on gastric functions, hormones and symptoms in functional dyspepsia and health: randomized crossover trial. Am J Physiol Gastrointest Liver Physiol 2020;318(4):G635-G645. PubMed
Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
Taking Secretin and Phentermine Together: Common Questions
Is it safe to take Secretin with Phentermine?
Do Secretin and Phentermine have any of the same side effects?
Does Phentermine interact with any supplements?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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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.