Drug & supplement interaction

Forsythia + Tenapanor Hydrochloride

Tenapanor Hydrochloride brand name: Ibsrela.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Forsythia and Tenapanor Hydrochloride 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

Forsythia and Tenapanor Hydrochloride

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 Tenapanor Hydrochloride and Forsythia 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.

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.

Forsythia safety at a glance

Forsythia overall Use caution Generally used short-term in traditional medicine, but human safety data are limited.
Pregnancy Avoid Not enough safety data; avoid during pregnancy.
Breastfeeding Avoid Not enough safety data; best avoided while breastfeeding.

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

Still wondering about combining Tenapanor Hydrochloride and Forsythia? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Tenapanor Hydrochloride

Interactions in our licensed database are recorded against drug classes, not just single drug names. Tenapanor Hydrochloride is filed under 2 classifications — cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. Forsythia has documented interactions with 2 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate) and azithromycin (zithromax) (minor) — and none of Tenapanor Hydrochloride’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Forsythia Does Interact With Other Medications

Forsythia has 122 moderate, 1 minor known drug interactions in our database — Tenapanor Hydrochloride isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Forsythia

Covers the 2,830 medications we’ve checked against Forsythia. Pick one to open its full report.

What to actually watch for

What Tenapanor Hydrochloride’s Own FDA Label Lists

This is not an interaction — none of it involves Forsythia. These are the most notable effects listed in the ADVERSE REACTIONS section of Tenapanor Hydrochloride’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.

  • Bloating or gas mentioned in 5.8% of FDA reports for Tenapanor Hydrochloride
  • Diarrhea mentioned in 31.1% of FDA reports for Tenapanor Hydrochloride
  • Dizziness

From the ADVERSE REACTIONS section of the FDA label for Tenapanor Hydrochloride. Read the label on DailyMed › Where a percentage is shown, it is the share of 1,216 voluntary FDA FAERS reports for Tenapanor Hydrochloride that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Forsythia’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Forsythia side to compare — that is a limit of the record, not a statement that Forsythia has no side effects.

Everything else you take

See Every Supplement That Interacts With Tenapanor Hydrochloride

This page covers Forsythia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tenapanor Hydrochloride page lists 138 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 94 moderate · 41 minor.

From our pharmacist’s overview on the Tenapanor Hydrochloride page

“Tenapanor hydrochloride (Ibsrela) works in the gut to relieve irritable bowel syndrome with constipation, and its supplement interaction list deserves genuine care rather than a quick skim. Three of the 138 ingredients on file rate major: grapefruit, St.”

Reviewed by 2 · Jul 18, 2026

Open the Tenapanor Hydrochloride interaction page

One more smart check

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

We hold 355 real supplement products containing Forsythia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Forsythia. Even though Forsythia itself has no known interaction with Tenapanor Hydrochloride, 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 Forsythia and Tenapanor Hydrochloride 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 Forsythia
Top 25%

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

29 days ago today
Medication Tenapanor Hydrochloride
Top 10%

#172 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 Forsythia reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Forsythia and Tenapanor Hydrochloride records this page draws on were last updated June 20, 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 Forsythia

What is Forsythia?

  • Colds and flu symptoms
  • Sore throat
  • Fever
  • Inflammation
  • Antimicrobial support

Forsythia is a traditional Chinese herb, used mainly for cold and flu symptoms and as part of multi-herb formulas. Most evidence comes from laboratory, animal, and traditional use rather than strong human studies, so its real-world benefits remain unproven. Talk to your pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or taking other medicines.

Forsythia suspensa · Oleaceae · Dried fruit (and sometimes leaves) · Dried fruit, teas, decoctions, capsules, and herbal formulas

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

Forsythia: dosing

There is no well-established standardized dose for forsythia. Traditional preparations use the dried fruit in decoctions, often as part of a multi-herb formula, and amounts vary by product and practitioner.If you use a commercial supplement, follow the directions on the product label and do not exceed the recommended amount.

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

Read the full Forsythia monograph & all interactions
Medication

About Tenapanor

What Is Tenapanor Used For?

Brand name: Ibsrela

Tenapanor is approved for two distinct conditions, each under a separate brand. Ibsrela is used to treat irritable bowel syndrome with constipation (IBS-C) in adults. XPHOZAH is used to reduce high phosphorus levels (hyperphosphatemia) in adults with chronic kidney disease (CKD) who are on dialysis — specifically as an add-on when phosphate binders haven't worked well enough or aren't tolerated.

Most-Reported Side Effects for Tenapanor Hydrochloride

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 1,239 reports
Therapy interrupted 292 reports
Abdominal distension 234 reports
Insurance issue 184 reports
Intentional underdose 167 reports
See full Tenapanor drug information
Keep checking

Other Drugs & Forsythia

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

0Major
122Moderate
1Minor
2,706No known interaction
Moderate

122 interactions

Showing 60 of 122 moderate interactions — see all 122 on the Forsythia page.

Minor

1 interaction

No interaction 2,706 drugs checked — show the list
Evidence & sources

Forsythia References

The 3 references that drive our Forsythia 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. Kong XT, Fang HT, Jiang GQ, et al. Treatment of acute bronchiolitis with Chinese herbs. Arch Dis Child 1993;68:468-71. PubMed
  2. Iwakami S, Wu JB, Ebizuka Y, Sankawa U. Platelet activating factor (PAF) antagonists contained in medicinal plants: lignans and sesquiterpenes. Chem Pharm Bull (Tokyo) 1992;40:1196-8. PubMed
  3. Li XG, Ni J, Shen S, Wang XP, Tian JC. Pharmacokinetic interaction of Forsythia suspensa extract and azithromycin injection after single and co-intravenous administration in rats. Chin J Nat Med 2020;18(3):234-240. 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 Forsythia and Tenapanor Hydrochloride Together: Common Questions

Is it safe to take Forsythia with Tenapanor Hydrochloride?
We do not list a known interaction between Forsythia and Tenapanor Hydrochloride. 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.
How was the Forsythia and Tenapanor Hydrochloride combination checked?
Interactions in our licensed database are recorded against drug classes. Tenapanor Hydrochloride is filed under 2 classifications, and Forsythia has documented interactions with 2 drug classes — none of Tenapanor Hydrochloride's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Forsythia interact with any other medications?
Yes. Forsythia has 123 documented drug interactions in our database — Tenapanor Hydrochloride is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Tenapanor Hydrochloride interact with any supplements?
Yes. Tenapanor Hydrochloride has documented interactions with 138 supplements in our database — Forsythia is not one of them. The Tenapanor Hydrochloride 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 Tenapanor Hydrochloride and Forsythia?

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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.