Drug & supplement interaction

Rose Hip + Mechlorethamine Hydrochloride

Mechlorethamine Hydrochloride brand name: Valchlor.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Rose Hip has a moderate interaction with Mechlorethamine Hydrochloride. Theoretically, the antioxidant effects of rose hip might reduce the effectiveness of alkylating agents but might also reduce the oxidative damage caused by certain alkylating agents.

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

Rose Hip and Mechlorethamine Hydrochloride

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

Moderate

ALKYLATING AGENTS

Why this applies to Mechlorethamine Hydrochloride

Mechlorethamine Hydrochloride falls under ALKYLATING AGENTS — the group Rose Hip interacts with.

Theoretically, the antioxidant effects of rose hip might reduce the effectiveness of alkylating agents but might also reduce the oxidative damage caused by certain alkylating agents.
Rose hip contains vitamin C. The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. Further, some animal research suggests that the antioxidant effects of rose hip might attenuate cyclophosphamide-induced testicular toxicity. More evidence is needed to determine what effect, if any, antioxidants found in rose hip, such as vitamin C, have on the effectiveness and adverse effects of chemotherapy.
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 gist with rose hip and your Valchlor gel. Rose hip is loaded with vitamin C and other antioxidants, and the worry on paper is that these antioxidants might blunt how well certain chemo drugs work, since some of them fight cancer partly by creating cellular stress. The flip side is that some researchers think antioxidants could actually help, so honestly the science pulls both directions and is far from settled.

I want to be straight with you: this is a theoretical concern based on how these drugs behave in the lab, not proven in people. Valchlor is also applied to your skin, so the amounts reaching your body are quite low. Eating rose hip in food is unlikely to matter, but please check with your oncology team before taking concentrated rose hip supplements during treatment.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  2. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  3. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  4. Parandin R, Ghowsi M, Dadbod A. Protective effects of hydroalcoholic extract of Rosa canina L. fruit on cyclophosphamide-induced testicular toxicity in mice. Avicenna J Phytomed 2023;13(1):7-17.

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

Rose Hip Also Interacts With Other Medications

Rose Hip has 212 moderate 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.

Moderate 212 No known interaction 2,618 (incl. Mechlorethamine Hydrochloride)
Taking anything else?

Check Another of Your Medications Against Rose Hip

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

From our Q&A

Questions About Rose Hip 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 Rose Hip 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 Rose Hip 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 Turmeric (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 Rose Hip as Part of a Dietary Supplement Product? Check It for Interactions

We hold 273 real supplement products containing Rose Hip, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Rose Hip. Your product may carry other ingredients that interact with Mechlorethamine Hydrochloride too, on top of Rose Hip — 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 Rose Hip 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 Rose Hip
Top 25%

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

29 days ago today
Medication Mechlorethamine Hydrochloride
Steady interest

#2,361 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 Rose Hip

What is Rose Hip?

Rose Hip
  • Joint pain and osteoarthritis
  • Colds and flu
  • Source of vitamin C
  • Digestive complaints
  • Anti-inflammatory support

Rose hip is the vitamin C–rich fruit of the wild rose, used traditionally for colds and joint pain. A standardized rose hip powder has some research support for easing osteoarthritis symptoms, but evidence for most other uses is limited. It is generally well tolerated as a food, but talk with your pharmacist or doctor before using it as a supplement.

Read the full Rose Hip 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 & Rose Hip

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

0Major
212Moderate
0Minor
2,617No known interaction
212 Moderate 2,617 No interaction
Moderate

212 interactions

Showing 60 of 212 moderate interactions — see all 212 on the Rose Hip page.

No interaction 2,617 drugs checked — show the list

We also checked Rose Hip against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,617 medications checked with no known interaction — see the full Rose Hip list.

See the full Rose Hip interactions page
See every supplement checked against Mechlorethamine Hydrochloride, ranked by severity
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

Keep exploring
Rose Hip monograph › Uses, safety, and every drug interaction in one place Mechlorethamine Hydrochloride supplement interactions › Every supplement checked against Mechlorethamine Hydrochloride, ranked by severity Mechlorethamine Topical drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Rose Hip and Mechlorethamine Hydrochloride Together: Common Questions

Can you take Rose Hip with Mechlorethamine Hydrochloride?
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 Rose Hip and Mechlorethamine Hydrochloride 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

Still Have a Question About Mechlorethamine Hydrochloride and Rose Hip?

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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.