Drug & supplement interaction

Shellac + Cholestyramine

Cholestyramine brand name: Questran.

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 Shellac and Cholestyramine 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.

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Interaction report

Shellac and Cholestyramine

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 Cholestyramine and Shellac 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 Shellac at all — not against Cholestyramine, 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.

Shellac safety at a glance

Shellac overall Use caution Generally regarded as safe as a coating in small amounts, but it is insect-derived and rare reactions can occur.
Pregnancy Use caution Likely fine in the tiny amounts used as a coating, but there is little specific safety data, so check with your doctor.
Breastfeeding Use caution Little specific data exists; the small amounts in coatings are unlikely to be a concern but caution is wise.

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

Still wondering about combining Cholestyramine and Shellac? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Shellac Itself Has Been Linked To

This is not an interaction — nothing below involves Cholestyramine. It is the side-effect record for Shellac on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Shellac, this list is the first place to look.

  • A skin rash Additional detail

    “Topically, there are numerous reports of allergic contact dermatitis and allergic contact cheilitis associated with shellac. Most cases of allergic dermatitis are related to shellac in mascara, especially Maybelline Great Lash mascara. However, cases of allergic contact dermatitis associated with shellac in tattoo ink and shellac in hair spray have been reported.”

    Shellac · Natural Medicines adverse-effect record, reported in dermatitis.

    6 sources cited
    1. 104260. González-Villanueva I, Hispn Ocete P, Silvestre Salvador JF. Allergic contact dermatitis caused by a black tattoo ink in a patient allergic to shellac. Contact Dermatitis. 2016;75(4):247-8. PubMed
    2. 104262. Shaw T, Oostman H, Rainey D, Storrs F. A rare eyelid dermatitis allergen: shellac in a popular mascara. Dermatitis. 2009;20(6):341-5. DOI
    3. 104263. Gallo R, Marro I, Pavesi A. Allergic contact dermatitis from shellac in mascara. Contact Dermatitis. 2005;53(4):238. PubMed
    4. 104264. Strauss RM, Orton DI. Allergic contact cheilitis in the United Kingdom: a retrospective study. Am J Contact Dermat. 2003;14(2):75-7. DOI
    5. 104265. Orton DI, Salim A, Shaw S. Allergic contact cheilitis due to shellac. Contact Dermatitis. 2001;44(4):250. PubMed
    6. 112297. Navarro-Triviño FJ. Allergic contact dermatitis from shellac in an ecological hair spray occurring in a patient with frontal fibrosing alopecia. Contact Dermatitis 2022;86(6):544-545. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Shellac — expand a row for the licensed statement it rests on. We haven’t matched Cholestyramine to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Cholestyramine.

Everything else you take

See Every Supplement That Interacts With Cholestyramine

This page covers Shellac only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cholestyramine page lists 19 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 9 moderate · 9 minor.

From our pharmacist’s overview on the Cholestyramine page

“Activated charcoal is the single major-rated interaction with cholestyramine (Questran), and it is the one to understand first, because charcoal adsorbs medicines in the gut and can cut how much of an oral drug reaches the body. That major sits at the top of a 19-ingredient list I would treat with genuine care, since almost everything…”

Reviewed by 2 · Jul 18, 2026

Open the Cholestyramine interaction page

How much people look this up

Where Shellac and Cholestyramine 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 Shellac
Top half

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

29 days ago today
Medication Cholestyramine
Steady interest

#2,708 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 Shellac reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Shellac and Cholestyramine 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 Shellac

What is Shellac?

Shellac
  • Coating for tablets and capsules
  • Glaze on candy and chocolates
  • Protective film over pills and supplements
  • Enteric-style coating to delay dissolving
  • Shiny coating on fruits and confections

Shellac is a natural resin made from the secretions of the lac insect, and it is used mainly as a glaze or coating on pills, candy, and some supplements rather than as an active ingredient you take for a health benefit. In the small amounts used for coatings it is generally considered safe for most people, but those avoiding insect-derived products or with known sensitivities may want to steer clear.

Resinous secretion of the lac insect (Kerria lacca) · Tablet and capsule coatings, candy and pill glazes, food glaze (confectioner's glaze)

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

Shellac: dosing

There is no established therapeutic dose for shellac, because it is not taken as an active ingredient. It is used in whatever small amount is needed to coat or glaze a product.If you are choosing a supplement, you do not need to dose shellac itself.

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

Read the full Shellac monograph & all interactions
Medication

About Cholestyramine Resin

What Is Cholestyramine Resin Used For?

Brand name: Questran

  • Cholestyramine is used with diet changes (restriction of cholesterol and fat intake) to reduce the amount of cholesterol and certain fatty substances in your blood. Accumulation of cholesterol and fats along the walls of your arteries (a process known as atherosclerosis) decreases blood flow and, therefore, the oxygen supply to your heart, brain, and other parts of your body. Lowering your blood level of cholesterol and fats may help to prevent heart disease, angina (chest pain), strokes, and heart attacks.

  • This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Most-Reported Side Effects for Cholestyramine

From FAERS, the FDA’s public side-effect reporting system (9,356 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 1,323 reports
Fatigue 728 reports
Nausea 635 reports
Arthralgia 530 reports
Headache 467 reports
See full Cholestyramine Resin drug information
Keep checking

Other Drugs & Shellac

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

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

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

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Shellac list.

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

Shellac References

The 8 references that drive our Shellac 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. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. González-Villanueva I, Hispn Ocete P, Silvestre Salvador JF. Allergic contact dermatitis caused by a black tattoo ink in a patient allergic to shellac. Contact Dermatitis. 2016;75(4):247-8. PubMed
  3. Shaw T, Oostman H, Rainey D, Storrs F. A rare eyelid dermatitis allergen: shellac in a popular mascara. Dermatitis. 2009;20(6):341-5. DOI
  4. Gallo R, Marro I, Pavesi A. Allergic contact dermatitis from shellac in mascara. Contact Dermatitis. 2005;53(4):238. PubMed
  5. Strauss RM, Orton DI. Allergic contact cheilitis in the United Kingdom: a retrospective study. Am J Contact Dermat. 2003;14(2):75-7. DOI
  6. Orton DI, Salim A, Shaw S. Allergic contact cheilitis due to shellac. Contact Dermatitis. 2001;44(4):250. PubMed
  7. Navarro-Triviño FJ. Allergic contact dermatitis from shellac in an ecological hair spray occurring in a patient with frontal fibrosing alopecia. Contact Dermatitis 2022;86(6):544-545. PubMed
  8. Mercader-García P, Ruiz-Gonzalez I, Gonzalez-Perez R, Sanz-Sanchez T, Sanchez-Pérez J, Borrego L; en representación de REIDAC. Contact Allergy to Shellac. Retrospective Cross-Sectional Study With Data From the Spanish Registry of Research in Contact Derma

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 Shellac and Cholestyramine Together: Common Questions

Is it safe to take Shellac with Cholestyramine?
We do not list a known interaction between Shellac and Cholestyramine. 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.
Does Cholestyramine interact with any supplements?
Yes. Cholestyramine has documented interactions with 19 supplements in our database — Shellac is not one of them. The Cholestyramine 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

Shellac monograph Uses, safety profile, and every drug interaction in one place Cholestyramine Resin drug information The full plain-English guide to this medication Cholestyramine supplement interactions Every supplement checked against Cholestyramine, 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 8 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Cholestyramine and Shellac?

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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.