Drug & supplement interaction

Tung Seed + Psyllium (OTC drug)

Psyllium (OTC drug) brand name: Metamucil.

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 Tung Seed and Psyllium (OTC drug) 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.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Tung Seed and Psyllium (OTC drug)

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 Psyllium (OTC drug) and Tung Seed 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 Tung Seed at all — not against Psyllium (OTC drug), 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.

Tung Seed safety at a glance

Tung Seed overall Avoid Tung seeds and oil are poisonous if eaten and are not safe as a supplement.
Pregnancy Likely Unsafe When used orally; avoid using. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally; avoid using. Read the full breastfeeding detail

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.

Still wondering about combining Psyllium (OTC drug) and Tung Seed? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Tung Seed Itself Has Been Linked To

This is not an interaction — nothing below involves Psyllium (OTC drug). It is the side-effect record for Tung Seed on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Tung Seed, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • A slow heartbeat / Confusion / Chest pain / Shortness of breath Worth acting on Additional detail

    “A 16-year-old patient presented with acute onset abdominal pain, chest pain, and profuse and persistent vomiting following ingestion of both a tea made from boiling a whole candlenut and the boiled candlenut itself. The patient was also found to have first-degree heart block that later progressed to Mobitz type I second degree heart block with occasional 2:1 block, requiring ICU admission and monitoring.”

    Tung Seed · Natural Medicines adverse-effect record, reported in diarrhea.

    3 sources cited
    1. 106671. O'Brien DR, Szymczuk V, Albaro CA. Weight loss supplement causing acute heart block in a child. Cardiol Young 2020;30(1):131-133. PubMed
    2. 111341. Lawani O, Winter M. Heart Block Initiated by Candlenut Ingestion. Case Rep Cardiol 2022;2022:3679968. PubMed
    3. 111343. Koons AL, Laubach LT, Katz KD, Beauchamp GA. Mobitz Type II Atrioventricular Heart Block After Candlenut Ingestion. J Am Osteopath Assoc. 2020;120(12):839-843. PubMed
  • Weight loss / Numbness or tingling / Tiredness Additional detail

    Recorded for Tung Seed in the same Natural Medicines adverse-effect record shown under A slow heartbeat / Confusion / Chest pain / Shortness of breath above.

  • Stomach pain / Diarrhea Additional detail

    “Orally, candlenut can cause severe abdominal pain, violent vomiting, and diarrhea (6,4502,106671,111341).”

    Tung Seed · Natural Medicines adverse-effect record, reported in diarrhea.

    4 sources cited
    1. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    2. 4502. Duke JA. CRC handbook of medicinal herbs. 1st ed. Boca Raton, FL: CRC Press, LLC, 1985.
    3. 106671. O'Brien DR, Szymczuk V, Albaro CA. Weight loss supplement causing acute heart block in a child. Cardiol Young 2020;30(1):131-133. PubMed
    4. 111341. Lawani O, Winter M. Heart Block Initiated by Candlenut Ingestion. Case Rep Cardiol 2022;2022:3679968. PubMed
  • A skin rash Additional detail

    “Topically, candlenut can cause acute dermatitis.”

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

    1 source cited
    1. 4502. Duke JA. CRC handbook of medicinal herbs. 1st ed. Boca Raton, FL: CRC Press, LLC, 1985.

Showing the 10 most notable of 12 recorded effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

Everything above comes from the Natural Medicines adverse-effect record for Tung Seed — expand a row for the licensed statement it rests on. We haven’t matched Psyllium (OTC drug) 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 Psyllium (OTC drug).

Special populations

Tung Seed in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Unsafe

When used orally; 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

Overlapping uses

What Psyllium (OTC drug) Is Prescribed For, and What Tung Seed Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Psyllium (OTC drug) is a prescription medicine with approved uses on its FDA label. Tung Seed is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Psyllium (OTC drug) is prescribed for: Psyllium is used to treat occasional constipation and help restore regularity. Most products indicate that a bowel movement generally occurs within 12 to 72 hours of taking a dose. This applies to psyllium capsule products such as Best Choice, Careone, fiber laxative, meijer fiber laxative, Premier Value Fiber, and Publix, as well as oral powder products including Best Choice Fiber Therapy, Careone, Daily Fiber, Dr. Fibra, meijer fiber therapy, and Meijer Natural Daily Fiber Sugar Free.

Tung Seed has been studied for:

  • Constipation studied, not established Tung Seed has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Tung Seed for constipation

    Although there has been interest in using topical candlenut for constipation, there is insufficient reliable information about the clinical effects of candlenut for this purpose.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Psyllium (OTC drug) on your own; if you are taking Tung Seed for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Tung Seed or Psyllium (OTC drug)

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Tung Seed or Psyllium (OTC drug), 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:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Psyllium (OTC drug)

This page covers Tung Seed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Psyllium (OTC drug) page lists 17 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 · 7 moderate · 9 minor.

From our pharmacist’s overview on the Psyllium (OTC drug) page

“Activated charcoal tops the psyllium (Metamucil) list and is the one entry rated major. Charcoal binds many medicines in the gut and can cut how much of them reaches the body, so pairing it with anything you take by mouth deserves real caution, and I would read that entry before the rest.”

Reviewed by 2 · Jul 18, 2026

Open the Psyllium (OTC drug) interaction page

How much people look this up

Where Tung Seed and Psyllium (OTC drug) 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 Tung Seed
Steady interest

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

29 days ago today
Medication Psyllium (OTC drug)
Top half

#889 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 Tung Seed reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Tung Seed and Psyllium (OTC drug) 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 Tung Seed

What is Tung Seed?

  • Wood finishing and varnish (industrial)
  • Traditional folk skin applications
  • Traditional laxative use (historical)
  • Traditional topical remedies

Tung seed comes from the tung tree (Vernicia fordii), and its main product is tung oil, which is used mostly as an industrial wood finish, not as a food or medicine. The raw seeds and oil are toxic if swallowed and there is no reliable evidence supporting any health benefit. We do not recommend taking tung seed as a supplement.

Vernicia fordii · Euphorbiaceae · Seeds and the oil pressed from them (tung oil) · Tung oil (industrial), rarely available as a dietary supplement

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

Tung Seed: dosing

There is no established or safe dose of tung seed for use in people. Because the seeds and oil are toxic, no medical dosing exists, and we do not recommend taking it in any amount.If you see a product that claims to contain tung seed for health purposes, do not use it without first checking with a pharmacist or doctor. In general, tung oil should be treated as an industrial product only.

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

Read the full Tung Seed monograph & all interactions
Medication

About Psyllium

What Is Psyllium Used For?

Brand name: Metamucil

Psyllium is used to treat occasional constipation and help restore regularity. Most products indicate that a bowel movement generally occurs within 12 to 72 hours of taking a dose.

This applies to psyllium capsule products such as Best Choice, Careone, fiber laxative, meijer fiber laxative, Premier Value Fiber, and Publix, as well as oral powder products including Best Choice Fiber Therapy, Careone, Daily Fiber, Dr. Fibra, meijer fiber therapy, and Meijer Natural Daily Fiber Sugar Free.

See full Psyllium drug information
Keep checking

Other Drugs & Tung Seed

Browse every other medication we’ve checked against Tung Seed — 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 Tung Seed 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 Tung Seed list.

See the full Tung Seed interactions page
See every supplement checked against Psyllium (OTC drug), ranked by severity
Evidence & sources

Tung Seed References

The 5 references that drive our Tung Seed 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. Duke JA. CRC handbook of medicinal herbs. 1st ed. Boca Raton, FL: CRC Press, LLC, 1985.
  3. O'Brien DR, Szymczuk V, Albaro CA. Weight loss supplement causing acute heart block in a child. Cardiol Young 2020;30(1):131-133. PubMed
  4. Lawani O, Winter M. Heart Block Initiated by Candlenut Ingestion. Case Rep Cardiol 2022;2022:3679968. PubMed
  5. Koons AL, Laubach LT, Katz KD, Beauchamp GA. Mobitz Type II Atrioventricular Heart Block After Candlenut Ingestion. J Am Osteopath Assoc. 2020;120(12):839-843. 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 Tung Seed and Psyllium (OTC drug) Together: Common Questions

Is it safe to take Tung Seed with Psyllium (OTC drug)?
We do not list a known interaction between Tung Seed and Psyllium (OTC drug). 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.
Are Tung Seed and Psyllium (OTC drug) used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Tung Seed in each. That is a conversation for your prescriber, especially if Psyllium (OTC drug) is being adjusted to a target.
Does Psyllium (OTC drug) interact with any supplements?
Yes. Psyllium (OTC drug) has documented interactions with 17 supplements in our database — Tung Seed is not one of them. The Psyllium (OTC drug) 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

Tung Seed monograph Uses, safety profile, and every drug interaction in one place Psyllium drug information The full plain-English guide to this medication Psyllium (OTC drug) supplement interactions Every supplement checked against Psyllium (OTC drug), 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 5 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Psyllium (OTC drug) and Tung Seed?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.