Drug & supplement interaction

Arrach + Trioxsalen

Trioxsalen brand name: Trisoralen.

Moderate Interaction
The bottom line Moderate

Arrach has a moderate interaction with Trioxsalen. Theoretically, concomitant use of arrach can increase risk of adverse effects, as unspecified Chenopodium species are associated with photosensitivity.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Arrach and Trioxsalen

Here is the interaction we found between these two, with the evidence behind it.

Moderate

PHOTOSENSITIZING DRUGS

Why this applies to Trioxsalen

Trioxsalen falls under PHOTOSENSITIZING DRUGS — the group Arrach interacts with.

Theoretically, concomitant use of arrach can increase risk of adverse effects, as unspecified Chenopodium species are associated with photosensitivity.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the thing about Trioxsalen (Trisoralen): it's a medicine that deliberately makes your skin much more sensitive to UV light, which is why it's paired with light therapy for skin conditions like vitiligo. Your skin is already primed to react strongly to sunlight while you're using it.

Now, some plants in the goosefoot family (which includes Arrach) have been linked to photosensitivity, meaning they may also make skin react to light. So in theory, stacking these two together could pile on extra sun sensitivity, raising the chance of sunburn, redness, blistering, or skin damage. I'll be honest though, this concern is theoretical and based on pharmacology, not solid studies on Arrach itself. Still, since the risk runs the same direction, it's worth checking with your pharmacist or doctor before combining them.

References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Arrach Also Interacts With Other Medications

Arrach has 334 moderate known drug interactions in our database — the Trioxsalen one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Arrach

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

Everything else you take

See Every Supplement That Interacts With Trioxsalen

This page covers Arrach only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Trioxsalen page lists 37 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alfalfa (moderate), Angelica Archangelica (moderate), Bergamot (moderate) and Bishop's Weed (moderate).

By severity: 1 major · 26 moderate · 10 minor.

From our pharmacist’s overview on the Trioxsalen page

“Trioxsalen (Trisoralen) works by making skin extra sensitive to UVA light for psoriasis and vitiligo treatment, and that mechanism is exactly why this list deserves careful reading rather than a skim. Twenty of the 37 supplements and herbs on file add a photosensitizing effect of their own on top of the drug's, raising the odds of a bu…”

Reviewed by 2 · Jul 18, 2026

Open the Trioxsalen interaction page

How much people look this up

Where Arrach and Trioxsalen 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 Arrach
Top half

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

29 days ago today
Medication Trioxsalen
Steady interest

#2,801 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.

Supplement

About Arrach

What is Arrach?

Arrach
  • Painful menstruation
  • Nervous complaints
  • Digestive upset
  • Wound care
  • Insect repellent

Arrach (Chenopodium vulvaria) is a strong-smelling European herb that has been used in traditional folk medicine, mainly for menstrual and nervous complaints. There is very little modern scientific evidence to show that it works or is safe, so it is not recommended, especially during pregnancy or breastfeeding. Talk to your pharmacist or doctor before using any herbal product.

Read the full Arrach monograph & all interactions
Keep checking

Other Drugs & Arrach

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

0Major
334Moderate
0Minor
2,495No known interaction
Moderate

334 interactions

Showing 60 of 334 moderate interactions — see all 334 on the Arrach page.

No interaction 2,495 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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 Arrach and Trioxsalen Together: Common Questions

Can you take Arrach with Trioxsalen?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Arrach and Trioxsalen interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

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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.