Drug & supplement interaction

Alchemilla + Mechlorethamine Hydrochloride

Mechlorethamine Hydrochloride brand name: Valchlor.

Minor Interaction
The bottom line Minor

Alchemilla has a minor interaction with Mechlorethamine Hydrochloride. While no side effects have been reported from orally using Alchemilla, a clinical study titled "Treatment of Aphthous Stomatitis with Topical Alchemilla vulgaris in Glycerine," published in Clinical Drug Investigation (https://pubmed.ncbi.nlm.nih.gov/17163290/), found that local mouth irritation occ...

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

Alchemilla and Mechlorethamine Hydrochloride

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

Minor

Topical Drugs

Why this applies to Mechlorethamine Hydrochloride

Mechlorethamine Hydrochloride falls under Topical Drugs — the group Alchemilla interacts with.

While no side effects have been reported from orally using Alchemilla, a clinical study titled "Treatment of Aphthous Stomatitis with Topical Alchemilla vulgaris in Glycerine," published in Clinical Drug Investigation (https://pubmed.ncbi.nlm.nih.gov/17163290/), found that local mouth irritation occurred after applying a commercial product containing 3% alchemilla extract and glycerol (Aphtarine, Laboratoires Biosphere). Aphtarine was non-irritating in 68.2% of cases within 2-3 days, in 18.8% of cases within 4-7 days, and in 13.6% of cases with moderate irritation. Theoretically, combining Alchemilla with other potentially irritating topical products could increase the risk of local irritation and discomfort. The drug in this drug interaction monograph is available in a topical dosage form. There is no interaction expected from the oral dosage form of the drug.
Severity Minor 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 simple version: this isn't about how your body breaks down mechlorethamine. Valchlor is a gel you rub on your skin, and the only real overlap with Alchemilla is skin irritation. Mechlorethamine gel already tends to cause redness, itching, dryness, and sometimes mild burning where you apply it. Alchemilla used on the skin can also be irritating in some people, thanks to its astringent tannins.

So if you were to put a topical Alchemilla product on the same area, you might just add to that local irritation and discomfort. This is a minor, theoretical concern based on weak evidence, not a dangerous reaction. Taking Alchemilla by mouth shouldn't affect your Valchlor at all. Still, run any skin products past your pharmacist or oncologist first.

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

Alchemilla Also Interacts With Other Medications

Alchemilla has 197 minor known drug interactions in our database — the Mechlorethamine Hydrochloride 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 Alchemilla

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

From our Q&A

Questions About Alchemilla or Mechlorethamine Hydrochloride

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Alchemilla or Mechlorethamine Hydrochloride, 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 Mechlorethamine Hydrochloride

This page covers Alchemilla only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Mechlorethamine Hydrochloride page lists 10 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Acerola (moderate), Alpha-lipoic Acid (moderate), Coenzyme Q10 (moderate), Dimethylsulfoxide (dmso) (moderate) and Rose Hip (moderate).

By severity: 9 moderate · 1 minor.

From our pharmacist’s overview on the Mechlorethamine Hydrochloride page

“Mechlorethamine (Valchlor) is a chemotherapy gel applied to the skin for a form of lymphoma, and the 10 supplements on this page split into two groups. Seven are antioxidants, everyday products like vitamin C and turmeric, which in theory could blunt how well an alkylating chemotherapy drug works.”

Reviewed by 2 · Jul 18, 2026

Open the Mechlorethamine Hydrochloride interaction page

One more smart check

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

We hold 19 real supplement products containing Alchemilla, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Alchemilla. Your product may carry other ingredients that interact with Mechlorethamine Hydrochloride too, on top of Alchemilla — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Alchemilla and Mechlorethamine 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 Alchemilla
Top half

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

29 days ago today
Medication Mechlorethamine Hydrochloride
Steady interest

#1,725 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 Alchemilla

What is Alchemilla?

Alchemilla
  • Menstrual and women's health complaints
  • Diarrhea and digestive upset
  • Wound healing (topical)
  • Skin moisturizing (topical)
  • Mild inflammation

Alchemilla (lady's mantle) is a European herb traditionally used for digestive complaints, women's health issues, and as an astringent for skin and wounds. Solid human research is very limited, so its benefits remain largely unproven, and it should be avoided in pregnancy and breastfeeding due to a lack of safety data.

Read the full Alchemilla monograph & all interactions
Medication

About Mechlorethamine Topical

What Is Mechlorethamine Topical Used For?

Brand name: Valchlor

Valchlor (mechlorethamine gel applied to the skin) is approved to treat Stage IA and IB mycosis fungoides-type cutaneous T-cell lymphoma — a slow-growing cancer that primarily affects the skin. It is used in patients who have already received at least one prior skin-directed treatment.

See full Mechlorethamine Topical drug information
Keep checking

Other Drugs & Alchemilla

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

0Major
0Moderate
197Minor
2,632No known interaction
Minor

197 interactions

Showing 60 of 197 minor interactions — see all 197 on the Alchemilla page.

No interaction 2,632 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 Alchemilla and Mechlorethamine Hydrochloride Together: Common Questions

Can you take Alchemilla with Mechlorethamine Hydrochloride?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Alchemilla and Mechlorethamine Hydrochloride interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Mechlorethamine Hydrochloride and Alchemilla?

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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.