Drug & supplement interaction

Plant Sterols + Propylthiouracil, PTU

Propylthiouracil, PTU brand name: Propylthiouracil.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Plant Sterols and Propylthiouracil, PTU 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 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.

Know someone taking this? Share
Interaction report

Plant Sterols and Propylthiouracil, PTU

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 Propylthiouracil, PTU and Plant Sterols 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 Plant Sterols at all — not against Propylthiouracil, PTU, 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.

Plant Sterols safety at a glance

Plant Sterols overall Generally safe Generally well tolerated at typical food and supplement amounts for most adults.
Pregnancy Use caution Safety of concentrated supplements during pregnancy is not well studied, so use caution and check with your doctor.
Breastfeeding Use caution There is limited information on concentrated supplements during breastfeeding, so caution is advised.

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

Still wondering about combining Propylthiouracil, PTU and Plant Sterols? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Plant Sterols and Propylthiouracil, PTU May Share a Side Effect

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.

  • A skin rash Additional detail

    Plant Sterols

    “Acute dermatitis has been reported in a case report of a 51-year-old female who used a pharmacy-brand plant sterol supplement to lower cholesterol levels. The rash was widespread with lesions on the hands and feet and a red and swollen face. The patient was treated orally with prednisolone and topically with emollients for 2 weeks.”

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

    1 source cited
    1. 90737. Haque Hussain SS, Weir J, Roberts N. Severe dermatitis secondary to plant sterol supplements. Clin Exp Dermatol. 2009 Oct;34(7):e276-7. PubMed

    Propylthiouracil, PTU

    Listed in the ADVERSE REACTIONS section of the FDA label for Propylthiouracil, PTU. Read the label on DailyMed ›

Reported for Plant Sterols but not commonly for Propylthiouracil, PTU: stomach upset, diarrhea and acne.

Effects for Propylthiouracil, PTU come from the ADVERSE REACTIONS section of its FDA label; effects for Plant Sterols come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 2,019 voluntary FDA FAERS reports for Propylthiouracil, PTU that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

From our Q&A

Questions About Plant Sterols or Propylthiouracil, PTU

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Plant Sterols or Propylthiouracil, PTU, 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 Propylthiouracil, PTU

This page covers Plant Sterols only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Propylthiouracil, PTU page lists 64 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Siberian Cocklebur (major), Wine (major) and Ascophyllum Nodosum (moderate).

By severity: 4 major · 51 moderate · 9 minor.

Open the Propylthiouracil, PTU interaction page

One more smart check

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

We hold 28 real supplement products containing Plant Sterols, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Plant Sterols. Even though Plant Sterols itself has no known interaction with Propylthiouracil, PTU, 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 Plant Sterols and Propylthiouracil, PTU 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 Plant Sterols
Top half

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

29 days ago today
Medication Propylthiouracil, PTU
Top half

#983 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 Plant Sterols reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Plant Sterols and Propylthiouracil, PTU 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 Plant Sterols

What is Plant Sterols?

  • High cholesterol
  • Heart health support
  • Lowering LDL cholesterol

Plant sterols (and their close relatives, plant stanols) are natural compounds found in plants that can modestly lower LDL ('bad') cholesterol when taken regularly in adequate amounts, usually through fortified foods or supplements. They are widely considered a useful add-on to a heart-healthy diet, but they are not a replacement for prescribed cholesterol medicine. Talk with your pharmacist or doctor before starting them, especially if you take cholesterol drugs.

Sterols extracted from plant oils, nuts, seeds, grains, and legumes · Capsules, softgels, fortified margarine/spreads, fortified yogurt and milk, powders

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

Plant Sterols: dosing

There is no single official dose for everyone, but cholesterol-lowering benefits are generally seen only when enough is taken consistently each day, usually spread across meals. Taking them with food is often recommended, since they work by affecting how cholesterol is absorbed during digestion.The best approach is to follow the directions on your specific product label, since fortified foods and supplements vary in strength.

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

Read the full Plant Sterols monograph & all interactions
Medication

About Propylthiouracil

What Is Propylthiouracil Used For?

Brand name: Propylthiouracil

Propylthiouracil tablets are used to treat hyperthyroidism — a condition where the thyroid gland makes too much thyroid hormone. It is specifically indicated for patients with Graves' disease or toxic multinodular goiter who cannot tolerate methimazole (another antithyroid drug) and for whom surgery or radioactive iodine is not a suitable option.

It is also used to bring thyroid hormone levels under control before a patient undergoes thyroidectomy (thyroid surgery) or radioactive iodine therapy, again in patients who cannot tolerate methimazole. Because of its serious liver risks, propylthiouracil is generally a second-choice treatment — used when other options are not appropriate.

See full Propylthiouracil drug information
Keep checking

Other Drugs & Plant Sterols

Browse every other medication we’ve checked against Plant Sterols — 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
No interaction 2,829 drugs checked — show the list
Evidence & sources

Plant Sterols References

The 3 references that drive our Plant Sterols 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. Guardamagna, O., Abello, F., Baracco, V., Federici, G., Bertucci, P., Mozzi, A., Mannucci, L., Gnasso, A., and Cortese, C. Primary hyperlipidemias in children: effect of plant sterol supplementation on plasma lipids and markers of cholesterol synthesis a
  2. Haque Hussain SS, Weir J, Roberts N. Severe dermatitis secondary to plant sterol supplements. Clin Exp Dermatol. 2009 Oct;34(7):e276-7. PubMed
  3. Xue P, Wang Y, Chen Y, et al. A Case of Peripheral Precocious Puberty May Be Caused by a Diet Containing Phytosterols in a 20-Month-Old Boy. Horm Res Paediatr 2022;95(5):484-491. 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 Plant Sterols and Propylthiouracil, PTU Together: Common Questions

Is it safe to take Plant Sterols with Propylthiouracil, PTU?
We do not list a known interaction between Plant Sterols and Propylthiouracil, PTU. 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 Plant Sterols and Propylthiouracil, PTU have any of the same side effects?
Yes — our sources link each of them separately to one 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.
Does Propylthiouracil, PTU interact with any supplements?
Yes. Propylthiouracil, PTU has documented interactions with 64 supplements in our database — Plant Sterols is not one of them. The Propylthiouracil, PTU interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Propylthiouracil, PTU and Plant Sterols?

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.