Gelatin + Methylnaltrexone
Methylnaltrexone brand name: Relistor.
We found no known interaction between Gelatin and Methylnaltrexone 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 label for Methylnaltrexone states a food rule worth keeping to, and 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.
Gelatin and Methylnaltrexone
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 Methylnaltrexone and Gelatin 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 Gelatin at all — not against Methylnaltrexone, 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.
Gelatin safety at a glance
Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Gelatin in Pregnancy & Breastfeeding
When used orally in the amounts commonly found in foods.
When a specific type of gelatin from donkey hide, called colla corii asini, is used orally in doses of 10 grams daily for 6 weeks. Higher doses of 15 grams daily have been associated with an increased risk of inflammatory adverse effects, including sore throat, swollen gums, local eczema, and ulcers in the oral cavity. There is insufficient reliable information available about the safety of other types of gelatin when used during pregnancy in medicinal amounts.
When used orally in the amounts commonly found in foods. There is insufficient reliable information available about the safety of using larger amounts of gelatin during lactation; avoid using.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center
Some Methylnaltrexone Products Have a Food Rule — Gelatin Should Not Break It
At least one FDA label for a product containing Methylnaltrexone says to take it on an empty stomach. Most supplements — Gelatin included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Methylnaltrexone on its own and move Gelatin to a meal later in the day.
This may not be true of your version. Food instructions belong to the product, not the ingredient: two Methylnaltrexone products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.
o In patients with chronic non-cancer pain and OIC, take RELISTOR tablets with water on an empty stomach at least 30 minutes before the first meal of the day.
From the Dosage and Administration section of the FDA label we read for Methylnaltrexone — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›
A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.
See Every Supplement That Interacts With Methylnaltrexone
This page covers Gelatin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Methylnaltrexone page lists 3 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Fever Bark (moderate), Iboga (moderate) and Yohimbe (moderate).
By severity: 3 moderate.
From our pharmacist’s overview on the Methylnaltrexone page
“If you take methylnaltrexone (Relistor) for opioid-induced constipation, the supplement list to know is short: three ingredients, all rated moderate, none major. Yohimbe, fever bark, and iboga are all cleared by the same liver enzyme, CYP2D6, and methylnaltrexone can slow that enzyme, letting their active compounds build up in your blood.”
Reviewed by 2 · Jul 18, 2026
Taking Gelatin as Part of a Dietary Supplement Product? Check It for Interactions
We hold 269 real supplement products containing Gelatin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Gelatin. Even though Gelatin itself has no known interaction with Methylnaltrexone, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:
Where Gelatin and Methylnaltrexone 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.
#529 of 1,452 supplements looked up here in the last 7 days
#2,469 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 Gelatin reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Gelatin and Methylnaltrexone records this page draws on were last updated July 11, 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 Gelatin
What is Gelatin?
- Joint and bone health
- Skin, hair, and nail support
- Source of dietary protein
- Digestive comfort
- Capsule shells for medicines and supplements
Gelatin is a protein made from animal collagen, used as a food, a capsule ingredient, and a supplement for joint, skin, and bone health. For most health uses, the evidence is limited or mixed, though it is generally safe as a food. If you have allergies, dietary restrictions, or a health condition, check with your pharmacist or doctor first.
Collagen derived from animal skin, bones, and connective tissue (usually pork or beef) · Powder, capsules, gummies, food products (Jell-O type desserts), and collagen/gelatin drinks
An interaction check asks whether these two react with each other — it does not ask whether Gelatin is a good idea for someone in your situation. Here is what our Gelatin record says about it on its own.
Gelatin: dosing
There is no official, standardized dose of gelatin for any health condition. The amount used in studies varies widely, and it is not clear what dose, if any, provides a health benefit.If you choose to use a gelatin supplement, follow the directions on the product label and do not exceed the recommended amount.
From our Gelatin monograph — the full record covers uses, side effects and every documented interaction.
About Methylnaltrexone
What Is Methylnaltrexone Used For?
Brand name: Relistor
Methylnaltrexone, sold as Relistor, treats opioid-induced constipation (OIC) — constipation caused by opioid pain medications. Both Relistor tablets and Relistor injection are approved for adults with chronic non-cancer pain, including those with pain related to a prior cancer or its treatment who do not need frequent opioid dose increases.
Relistor injection is also approved for adults with advanced illness or active cancer pain who require increasing opioid doses as part of palliative care.
Other Drugs & Gelatin
Browse every other medication we’ve checked against Gelatin — 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 Gelatin against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Sertraline ›
- Testosterone ›
- Losartan Potassium ›
- Ivermectin ›
- Abemaciclib ›
- Aspirin ›
- Acetaminophen ›
- Metoprolol ›
- Rosuvastatin ›
- Rivaroxaban ›
- Escitalopram ›
- Clopidogrel ›
- Atorvastatin ›
- Tadalafil ›
- Docusate ›
- Tirzepatide ›
- Ibuprofen ›
- Methamphetamine ›
- Hydroxyurea ›
- Warfarin Sodium ›
- Valacyclovir ›
- Sumatriptan ›
- Semaglutide ›
- Prednisone ›
- Lisdexamfetamine ›
- Propranolol ›
- Metformin ›
- Amitriptyline ›
- Amoxicillin ›
- Lisinopril ›
- Isotretinoin ›
- Amlodipine Besylate ›
- Methotrexate ›
- Bendamustine ›
- Bupropion ›
- Amphetamine ›
- Doxycycline ›
- Fluoxetine ›
- Acyclovir ›
- Azithromycin ›
- Lamotrigine ›
- Pregabalin ›
- Dextroamphetamine ›
- Gabapentin ›
- Acetaminophen, Codeine ›
- Clonazepam ›
- Quetiapine ›
- Levothyroxine, Liothyronine ›
- Naproxen ›
- Omeprazole ›
- Letrozole ›
- Methylene Blue ›
- Duloxetine ›
- Buspirone ›
- Citalopram ›
Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Gelatin list.
Gelatin References
The 11 references that drive our Gelatin 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.
- Lewis CJ. Letter to reiterate certain public health and safety concerns to firms manufacturing or importing dietary supplements that contain specific bovine tissues. FDA. Available at: www.cfsan.fda.gov/~dms/dspltr05.html.
- Schwick HG, Heide K. Immunochemistry and immunology of collagen and gelatin. Bibl Haematol 1969;33:111-25. PubMed
- Moskowitz RW. Role of collagen hydrolysate in bone and joint disease.Semin Arthritis Rheum 2000;30:87-99. PubMed
- Kelso JM. The gelatin story. J Allergy Clin Immunol 1999;103:200-2.
- Nakayama T, Aizawa C, Kuno-Sakai H. A clinical analysis of gelatin allergy and determination of its causal relationship to the previous administration of gelatin-containing acellular pertussis vaccine combined with diphtheria and tetanus toxoids. J Allerg PubMed
- Sakaguchi M, Inouye S. Anaphylaxis to gelatin-containing rectal suppositories. J Allergy Clin Immunol 2001;108:1033-4. PubMed
- PDR Electronic Library. Montvale, NJ: Medical Economics Company, Inc., 2001.
- de la Fuente Tornero E, Vega Castro A, de Sierra Hernández PÁ, et al. Kounis syndrome during anesthesia: Presentation of indolent systemic mastocytosis: A case report. A Case Rep. 2017;8(9):226-228. PubMed
- Ventura Spagnolo E, Calapai G, Minciullo PL, Mannucci C, Asmundo A, Gangemi S. Lethal anaphylactic reaction to intravenous gelatin in the course of surgery. Am J Ther. 2016;23(6):e1344-e1346. PubMed
- Li Y, He H, Yang L, Li X, Li D, Luo S. Therapeutic effect of Colla corii asini on improving anemia and hemoglobin compositions in pregnant women with thalassemia. Int J Hematol. 2016;104(5):559-565. PubMed
- Coury JR, Skaggs KF, Marciano GF, et al. Intraoperative Anaphylaxis to the Bovine Flowable Gelatin Matrix: A Report of 2 Cases. JBJS Case Connect 2022;12(1). 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 Gelatin and Methylnaltrexone Together: Common Questions
Is it safe to take Gelatin with Methylnaltrexone?
Do Gelatin and Methylnaltrexone have any of the same side effects?
Should I take Gelatin and Methylnaltrexone at the same time of day?
Does Methylnaltrexone 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.