Drug & supplement interaction

Carob + Methylnaltrexone

Methylnaltrexone brand name: Relistor.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Carob 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.

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Interaction report

Carob 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 Carob 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.

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.

Carob safety at a glance

Carob overall Generally safe Carob is widely consumed as a food and is generally considered safe in normal food amounts.
Pregnancy Use caution Food amounts are likely fine, but concentrated supplement doses are not well studied, so use caution.
Breastfeeding Use caution Food amounts are likely fine, but there is little safety data on medicinal or supplement doses.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Methylnaltrexone and Carob? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Methylnaltrexone

Interactions in our licensed database are recorded against drug classes, not just single drug names. Methylnaltrexone is filed under a single classification — cytochrome p450 2d6 (cyp2d6) inhibitors. Carob has documented interactions with 1 drug class — the most serious being oral drugs (minor) — and none of Methylnaltrexone’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Carob Does Interact With Other Medications

Carob has 2,022 minor known drug interactions in our database — Methylnaltrexone isn’t one of them. If you take anything else, check it against the full list below.

Minor 2,022 No known interaction 808 (incl. Methylnaltrexone)
Taking anything else?

Check Another of Your Medications Against Carob

Covers the 2,830 medications we’ve checked against Carob. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Carob and Methylnaltrexone May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Diarrhea / Vomiting Additional detail

    Carob

    “A five month-old child who was allergic to an anti-regurgitation milk formula containing carob gum experienced urticaria, rash, and explosive vomiting within 30 minutes of administration of the formula. In a separate case, an 11-week-old infant with Down syndrome presented with persistent vomiting, watery diarrhea, and lethargy requiring IV hydration.”

    Carob · Natural Medicines adverse-effect record, reported in allergic rhinitis (hay fever).

    5 sources cited
    1. 39969. Savino, F., Muratore, M. C., Silvestro, L., Oggero, R., and Mostert, M. Allergy to carob gum in an infant. J.Pediatr.Gastroenterol.Nutr. 1999;29(4):475-476. DOI
    2. 104235. Jedrzejczyk M, Bartnik K, Funkowicz M, Toporowska-Kowalska E. FPIES Induced by Locust Bean Gum in an Infant. J Investig Allergol Clin Immunol. 2020;30(3):197-199. PubMed
    3. 97850. Komericki P, Kränke B. Immediate hypersensitivity to carob pods. Contact Dermatitis. 2009;61(4):239-40. PubMed
    4. 39987. van, der Brempt, X, Ledent, C., and Mairesse, M. Rhinitis and asthma caused by occupational exposure to carob bean flour. J.Allergy Clin.Immunol. 1992;90(6 Pt 1):1008-1010. PubMed
    5. 40015. Scoditti, A., Peluso, P., Pezzuto, R., Giordano, T., and Melica, A. Asthma to carob bean flour. Ann.Allergy Asthma Immunol. 1996;77(1):81. PubMed

    Methylnaltrexone

    Listed in the ADVERSE REACTIONS section of the FDA label for Methylnaltrexone. Read the label on DailyMed ›

Reported for Carob but not commonly for Methylnaltrexone: chest pain, hives, a stuffy or runny nose and tiredness.

Effects for Methylnaltrexone come from the ADVERSE REACTIONS section of its FDA label; effects for Carob come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

How to take them

Some Methylnaltrexone Products Have a Food Rule — Carob Should Not Break It

At least one FDA label for a product containing Methylnaltrexone says to take it on an empty stomach. Most supplements — Carob 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 Carob 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.

Everything else you take

See Every Supplement That Interacts With Methylnaltrexone

This page covers Carob 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

Open the Methylnaltrexone interaction page

One more smart check

Taking Carob as Part of a Dietary Supplement Product? Check It for Interactions

We hold 161 real supplement products containing Carob, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Carob. Even though Carob 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:

How much people look this up

Where Carob 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.

Supplement Carob
Top half

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

29 days ago today
Medication Methylnaltrexone
Steady interest

#2,565 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.

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 Carob reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Carob and Methylnaltrexone 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.
Data structure & sourcing designed and verified by .
Supplement

About Carob

What is Carob?

Carob
  • Diarrhea (especially in children)
  • Cocoa/chocolate substitute
  • Digestive upset
  • Acid reflux/heartburn
  • Source of dietary fiber

Carob is a Mediterranean tree whose pods are widely used as a caffeine-free, naturally sweet cocoa alternative and as a thickener (carob gum). It is mostly eaten as a food and is generally well tolerated, and carob pod preparations have some traditional and limited research use for diarrhea, but evidence for most medicinal claims is limited. Check with your pharmacist or doctor before using it as a treatment, especially for infants or children.

Ceratonia siliqua · Fabaceae · Pods (fruit), seeds, and seed gum · Carob powder (flour), carob gum (locust bean gum), carob syrup, chips, capsules

An interaction check asks whether these two react with each other — it does not ask whether Carob is a good idea for someone in your situation. Here is what our Carob record says about it on its own.

Carob: dosing

There is no official, standardized medicinal dose for carob. It is most often used as a food ingredient rather than a measured supplement.If you use a carob product such as a powder, syrup, or capsule, follow the directions on the product label.

From our Carob monograph — the full record covers uses, side effects and every documented interaction.

Read the full Carob monograph & all interactions
Medication

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.

See full Methylnaltrexone drug information
Keep checking

Other Drugs & Carob

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

0Major
0Moderate
2,022Minor
807No known interaction
2,022 Minor 807 No interaction
Minor

2,022 interactions

Showing 60 of 2,022 minor interactions — see all 2,022 on the Carob page.

No interaction 807 drugs checked — show the list

We also checked Carob against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 807 medications checked with no known interaction — see the full Carob list.

See the full Carob interactions page
See every supplement checked against Methylnaltrexone, ranked by severity
Evidence & sources

Carob References

The 9 references that drive our Carob 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.

  1. Savino, F., Muratore, M. C., Silvestro, L., Oggero, R., and Mostert, M. Allergy to carob gum in an infant. J.Pediatr.Gastroenterol.Nutr. 1999;29(4):475-476. DOI
  2. Bosscher, D., Caillie-Bertrand, M., and Deelstra, H. Effect of thickening agents, based on soluble dietary fiber, on the availability of calcium, iron, and zinc from infant formulas. Nutrition 2001;17(7-8):614-618. PubMed
  3. van, der Brempt, X, Ledent, C., and Mairesse, M. Rhinitis and asthma caused by occupational exposure to carob bean flour. J.Allergy Clin.Immunol. 1992;90(6 Pt 1):1008-1010. PubMed
  4. Clarke, P. and Robinson, M. J. Thickening milk feeds may cause necrotising enterocolitis. Arch Dis.Child Fetal Neonatal Ed 2004;89(3):F280. PubMed
  5. Harmuth-Hoene, A. E. and Schelenz, R. Effect of dietary fiber on mineral absorption in growing rats. J Nutr 1980;110(9):1774-1784. PubMed
  6. Scoditti, A., Peluso, P., Pezzuto, R., Giordano, T., and Melica, A. Asthma to carob bean flour. Ann.Allergy Asthma Immunol. 1996;77(1):81. PubMed
  7. Komericki P, Kränke B. Immediate hypersensitivity to carob pods. Contact Dermatitis. 2009;61(4):239-40. PubMed
  8. Bosscher D, Van Caillie-Bertrand M, Van Cauwenbergh R, Deelstra H. Availabilities of calcium, iron, and zinc from dairy infant formulas is affected by soluble dietary fibers and modified starch fractions. Nutrition. 2003;19(7-8):641-5. PubMed
  9. Jedrzejczyk M, Bartnik K, Funkowicz M, Toporowska-Kowalska E. FPIES Induced by Locust Bean Gum in an Infant. J Investig Allergol Clin Immunol. 2020;30(3):197-199. 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.

Pharmacist Counseling Corner

Taking Carob and Methylnaltrexone Together: Common Questions

Is it safe to take Carob with Methylnaltrexone?
We do not list a known interaction between Carob and Methylnaltrexone. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Carob and Methylnaltrexone have any of the same side effects?
Yes — our sources link each of them separately to 2 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take Carob and Methylnaltrexone at the same time of day?
At least one FDA label for a product containing Methylnaltrexone says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Methylnaltrexone on its own and move Carob to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
How was the Carob and Methylnaltrexone combination checked?
Interactions in our licensed database are recorded against drug classes. Methylnaltrexone is filed under 1 classification, and Carob has documented interactions with 1 drug class — none of Methylnaltrexone's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Carob interact with any other medications?
Yes. Carob has 2,022 documented drug interactions in our database — Methylnaltrexone is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Methylnaltrexone interact with any supplements?
Yes. Methylnaltrexone has documented interactions with 3 supplements in our database — Carob is not one of them. The Methylnaltrexone interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Carob monograph Uses, safety profile, and every drug interaction in one place Methylnaltrexone drug information The full plain-English guide to this medication Methylnaltrexone supplement interactions Every supplement checked against Methylnaltrexone, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 9 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Methylnaltrexone and Carob?

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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.