Inactive ingredients by manufacturer

Methylnaltrexone inactive ingredients by manufacturer

Wondering whether your Methylnaltrexone has lactose, gluten, soy, a dye or gelatin in it? The medicine is the same, but the fillers, coatings and colors differ from one company to the next. This page shows what each Methylnaltrexone product's FDA label lists, so you can find a version that leaves out what you avoid and ask your pharmacist for it by its NDC.

We have read the FDA labels of 2 of the 3 current Methylnaltrexone products on the market today, from 1 company listing it with the FDA, and lined them up side by side. 1 label has no inactive-ingredient list we could read, so that product cannot be compared.

Ask about your bottle

Is there something in your Methylnaltrexone? Ask in plain words.

Name the company, strength or the NDC on your bottle and the ingredient you avoid. The answer comes only from the FDA labels on this page.

Answers are drawn from the FDA label data on this page and checked against it. They are not medical advice: confirm with your pharmacist before relying on them.

The short answer

Which Methylnaltrexone products list lactose, a gluten source, soy, dyes or gelatin?

  1. LactoseNo checked product

    No checked Methylnaltrexone product lists lactose.

  2. Wheat or gluten sourceNo checked product

    No checked Methylnaltrexone product lists a wheat or gluten source.

  3. SoyNo checked product

    No checked Methylnaltrexone product lists soy.

  4. Synthetic dyesNo checked product

    No checked Methylnaltrexone product lists synthetic dyes.

  5. GelatinNo checked product

    No checked Methylnaltrexone product lists gelatin.

Find a version without it

Every current Methylnaltrexone product and what its label lists

No checked product lists any of the concerns we look for.

ProductListsInactive ingredients on the label
Salix Pharmaceuticals, Inc. 3 products
8 mg/0.4 mL injectionNDC 65649-0552-04 None of these listed
Show 4 ingredients

EDETATE CALCIUM DISODIUM, GLYCINE HYDROCHLORIDE, SODIUM CHLORIDE, WATER
12 mg/0.6 mL injectionNDC 65649-0551-02 None of these listed
Show 4 ingredients

EDETATE CALCIUM DISODIUM, GLYCINE HYDROCHLORIDE, SODIUM CHLORIDE, WATER
150 mg tabletNDC 65649-0150-06 No inactive-ingredient list on the label No list we could read

A product with none of these listed is not certified to be without them: the label says what the manufacturer declared, and the source of a starch or a flavor is often not stated. The companies are the FDA's labelers, which include repackagers and distributors selling another company's product under their own label. The NDC opens the product's own page, with the full label and its inactive-ingredient notes.

At the pharmacy counter

How to use this at the pharmacy counter

  1. Pick the company whose list suits you and copy the NDC from the table. Many pharmacies order from wholesalers that carry several companies' versions and can request a particular one if you ask before the prescription is filled; some buy from one contracted source only, and a few insurance plans cover only certain NDCs, so ask the pharmacist to check.
  2. Treat "does not list" as exactly that. The label is what the manufacturer declared; a flavor or a starch may have an unstated source, and lines change. For celiac disease or a serious allergy, ask the manufacturer's medical information line for a written statement about the lot you have.
  3. Check the bottle each refill. A different company usually means a different shape, color and inactive-ingredient list; the pharmacist can tell you who made it, and the two-NDC comparison shows the difference line by line.
  4. If you need one company's version kept constant, ask your prescriber to write that company or the NDC on the prescription and tell the pharmacy you need it held. Rules vary by state and plan, so confirm with the pharmacist.
Ask Dr. Staiger which Methylnaltrexone product suits you →

Common questions about Methylnaltrexone inactive ingredients

Is Methylnaltrexone gluten-free?
This page cannot certify any Methylnaltrexone product gluten-free; it reports what each label declares. Of the 2 products checked, none lists a wheat, barley, rye or gluten ingredient, and none lists a starch without a stated source. If you have celiac disease, ask the manufacturer's medical information line for a written gluten statement for the lot you have.
Does Methylnaltrexone contain lactose?
No checked Methylnaltrexone product lists lactose on its label. The lactose in a tablet or capsule is a small amount, but people with a milk allergy or a strong intolerance often prefer a version that does not list it.
Does Methylnaltrexone contain soy?
No checked Methylnaltrexone product lists a soy ingredient (soybean oil or soy lecithin) on its label. Soy lecithin is the usual form and the amount is small, but people with a soy allergy often prefer a version that does not list it.
Is there a dye-free Methylnaltrexone?
No checked Methylnaltrexone product lists a synthetic dye (an FD&C or D&C colorant) on its label. Colorants often differ by strength within one company's line, so compare the lists above strength by strength.
Does Methylnaltrexone contain gelatin?
No checked Methylnaltrexone product lists gelatin on its label. Gelatin is usually bovine or porcine and the label rarely says which; for kosher, halal or vegetarian needs, ask the manufacturer.
Why do the inactive ingredients differ between manufacturers?
A generic must match the brand's active ingredient, strength, dose form and how it is absorbed; its fillers, binders, coatings and colorants are the manufacturer's own choice. That is why one Methylnaltrexone product can list lactose and a dye while another from a different company lists neither.
Can my pharmacy give me a specific manufacturer's version?
Often, if you ask before the prescription is filled: many pharmacies order from wholesalers that carry several companies' versions and can request a particular one. Some pharmacies buy a generic from one contracted source only, and a few insurance plans cover only certain NDCs, so ask the pharmacist to check. Give them the NDC from this page; the company name alone is often enough.
How current is this list?
The products are the ones in the FDA's current NDC directory as of October 6, 2026, and each inactive-ingredient list is the manufacturer's FDA label as our label sync last read it. Formulations change, so check the label on your own bottle and ask your pharmacist if a refill looks different.

Sources: the products are the finished Methylnaltrexone products in the FDA's current NDC directory (openFDA), as of October 6, 2026; each inactive-ingredient list is the manufacturer's FDA Structured Product Label via DailyMed, as our label sync last read it. The concern groups are HelloPharmacist's classification of the names the label declares. Educational information only, not medical advice; confirm with your pharmacist before relying on a list. ← Back to the Methylnaltrexone guide