Drug & supplement interaction

Couch Grass + Liotrix

Liotrix brand names: Euthroid 3, Euthroid 1/2, Euthroid 1.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Couch Grass and Liotrix 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 Liotrix states a food rule worth keeping to.

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Interaction report

Couch Grass and Liotrix

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 Liotrix and Couch Grass 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 Couch Grass at all — not against Liotrix, 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.

Couch Grass safety at a glance

Couch Grass overall Use caution Generally considered well tolerated, but human safety data are limited.
Pregnancy Avoid Not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid Not enough safety information, so it is best avoided while breastfeeding.

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

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

What Liotrix’s Own FDA Label Lists

This is not an interaction — none of it involves Couch Grass. These are the most notable effects listed in the ADVERSE REACTIONS section of Liotrix’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • A change in thyroid levels Worth acting on
  • Bone thinning Worth acting on
  • Muscle weakness Worth acting on
  • A heart attack Worth acting on
  • Heart failure Worth acting on
  • Wheezing Worth acting on
  • Seizures Worth acting on
  • Chest pain Worth acting on
  • Shortness of breath Worth acting on
  • A severe allergic reaction Worth acting on

Showing the 10 most notable of 32 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Liotrix. Read the label on DailyMed › Couch Grass’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Couch Grass side to compare — that is a limit of the record, not a statement that Couch Grass has no side effects.

How to take them

Some Liotrix Products Have a Food Rule — Couch Grass Should Not Break It

At least one FDA label for a product containing Liotrix says to take it on an empty stomach. Most supplements — Couch Grass included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Liotrix on its own and move Couch Grass 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 Liotrix 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.

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 Liotrix

This page covers Couch Grass only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Liotrix page lists 38 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Tiratricol (major), Acetyl-l-carnitine (moderate), Alpha-lipoic Acid (moderate) and Ascophyllum Nodosum (moderate).

By severity: 2 major · 26 moderate · 10 minor.

From our pharmacist’s overview on the Liotrix page

“Liotrix (Euthroid) combines both thyroid hormones, and since steady hormone levels are the entire point of treatment, this list deserves a slow, serious read. Most entries fall into two camps: twenty-one ingredients act on the hormone itself, some boosting it and others blunting it, while another seventeen change how well the dose is a…”

Reviewed by 2 · Jul 18, 2026

Open the Liotrix interaction page

One more smart check

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

We hold 1,482 real supplement products containing Couch Grass, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Couch Grass. Even though Couch Grass itself has no known interaction with Liotrix, 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 Couch Grass and Liotrix 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 Couch Grass
Top 25%

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

29 days ago today
Medication Liotrix
Steady interest

#1,677 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.
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Couch Grass and Liotrix records this page draws on were last updated June 22, 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 Couch Grass

What is Couch Grass?

  • Urinary tract complaints
  • Mild bladder irritation
  • Increasing urine flow (diuretic)
  • Kidney 'gravel' or stones (traditional)
  • Soothing inflamed urinary passages
  • Sore throat or cough (traditional)

Couch grass is a common lawn weed whose rhizome has long been used in traditional European herbal medicine, mainly for urinary and bladder complaints. High-quality human studies are lacking, so its benefits are largely unproven. It is generally considered well tolerated, but you should talk to a pharmacist or doctor before using it, especially if you have kidney or heart problems.

Elymus repens · Poaceae · Dried rhizome (underground stem) and roots · Tea (infusion or decoction), liquid extract, tincture, capsules

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

Couch Grass: dosing

There is no well-established standardized dose of couch grass, because it has not been studied carefully in modern trials. Traditional preparations include teas made from the dried rhizome and liquid extracts or tinctures.The safest approach is to follow the directions on the product label and not exceed the recommended amount. If you take couch grass, drinking plenty of water is often advised, particularly when it is used for urinary complaints.

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

Read the full Couch Grass monograph & all interactions
Medication

About Liotrix

What Is Liotrix Used For?

Brand names: Euthroid 3, Euthroid 1/2, Euthroid 1

  • Liotrix is used to treat hypothyroidism (a condition that results when the thyroid gland does not produce enough thyroid hormone). Symptoms of hypothyroidism include lack of energy, depression, constipation, weight gain, hair loss, dry skin, dry coarse hair, muscle cramps, decreased concentration, aches and pains, swelling of the legs, and increased sensitivity to cold. When taken correctly, liotrix can reverse these symptoms. Liotrix is also used to treat goiter (enlarged thyroid gland). This medication is also used to test for hyperthyroidism (a condition where the thyroid gland produces too much thyroid hormone). Liotrix is in a class of medications called thyroid agents. It works by supplying the thyroid hormones normally produced by the body.

See full Liotrix drug information
Keep checking

Other Drugs & Couch Grass

Browse every other medication we’ve checked against Couch Grass — 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
Sources

Sources & How We Checked

We checked Couch Grass against Liotrix in the Natural Medicines interaction database and found no documented interaction on file. The medication overview comes from MedlinePlus, and supplement label details from the NIH Dietary Supplement Label Database.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Couch Grass and Liotrix Together: Common Questions

Is it safe to take Couch Grass with Liotrix?
We do not list a known interaction between Couch Grass and Liotrix. 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.
Should I take Couch Grass and Liotrix at the same time of day?
At least one FDA label for a product containing Liotrix 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 Liotrix on its own and move Couch Grass 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.
Does Liotrix interact with any supplements?
Yes. Liotrix has documented interactions with 38 supplements in our database — Couch Grass is not one of them. The Liotrix 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 Liotrix and Couch Grass?

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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.