Mechlorethamine: uses, dosing, side effects & brands
Mechlorethamine is a medicine sold in the U.S. under 2 brand and generic names, for hodgkin disease, mycosis fungoides and neoplasm metastasis. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats (across its forms)
- Hodgkin Disease, Mycosis Fungoides and Neoplasm Metastasis
- Available as
- Injectable · Topical
- Sold as
- 2 products — Mustargen and Valchlor
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How Valchlor is dosed
From the FDA label for Valchlor (application NDA202317). Other mechlorethamine products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
For topical dermatological use only ( 2.1 ). Apply a thin film once daily to affected areas of the skin ( 2.1 , 2.2 ). 2.1 Dosing and Dose Modification For Topical Dermatological Use Only Apply a thin film of VALCHLOR gel once daily to affected areas of the skin. Stop treatment with VALCHLOR for any grade of skin ulceration, blistering, or moderately-severe or severe dermatitis (i.e., marked skin redness with edema) [ see Warnings and Precautions ( 5.3 ) ]. Upon improvement, treatment with VALCHLOR can be restarted at a reduced frequency of once every 3 days. If reintroduction of treatment is tolerated for at least one week, the frequency of application can be increased to every other day for at least one week and then to once daily application if tolerated. 2.2 Application Instructions VALCHLOR is a cytotoxic drug. Follow applicable special handling and disposal procedures. 1 Patients must wash hands thoroughly with soap and water after handling or applying VALCHLOR. Caregivers must wear disposable nitrile gloves when applying VALCHLOR to patients and wash hands thoroughly with soap and water after removal of gloves. If there is accidental skin exposure to VALCHLOR, caregivers must immediately wash exposed areas thoroughly with soap and water for at least 15 minutes and remove contaminated clothing [ see Warnings and Precautions ( 5.2 ) ]. Patients or caregivers should follow…
Everything below is the FDA label for Valchlor (topical). Mechlorethamine is also sold as injectable, and those are different medicines to take — follow the label for the one you were prescribed.
Valchlor side effects
The following clinically significant adverse reactions are discussed in greater detail in other sections of the prescribing information: Mucosal or eye injury [ see Warnings and Precautions ( 5.1 ) ] Secondary exposure to VALCHLOR [ see Warnings and Precautions ( 5.2 ) ] Dermatitis [ see Warnings and Precautions ( 5.3 ) ] Non-melanoma skin cancer [ see Warnings and Precautions ( 5.4 ) ] The most common adverse reactions (≥5%) are dermatitis, pruritus, bacterial skin infection, skin ulceration or blistering, and hyperpigmentation ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Helsinn Therapeutics (U.S.), Inc., at 1-855-482-5245 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. In a randomized, observer-blinded, controlled trial, VALCHLOR 0.016% (equivalent to 0.02% mechlorethamine HCl) was compared to an Aquaphor ® -based mechlorethamine HCl 0.02% ointment (Comparator) [ see Clinical Studies ( 14 ) ]. The maximum duration of treatment was 12 months. Sixty-three percent (63%) of patients in the VALCHLOR arm and 67% in the comparator arm completed 12 months of…
Who shouldn’t take Valchlor
The use of VALCHLOR is contraindicated in patients with known severe hypersensitivity to mechlorethamine. Hypersensitivity reactions, including anaphylaxis, have occurred with topical formulations of mechlorethamine. Severe hypersensitivity to mechlorethamine ( 4 )
Valchlor drug interactions
No drug interaction studies have been performed with VALCHLOR. Systemic exposure has not been observed with topical administration of VALCHLOR; therefore, systemic drug interactions are not likely.
Every mechlorethamine product we track (2)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Pharmacy pays | |
|---|---|---|---|---|---|---|---|
| 1 | Not yet rated | Prescription | Injectable | No data | — | View → | |
| 2 | Not yet rated | Prescription | Topical | No data | — | View → |
What people report to the FDA about mechlorethamine
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 103 reports naming mechlorethamine, and the FDA flagged 95% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- cutaneous t-cell lymphoma9 reports
- skin lesion9 reports
- erythema7 reports
- application site erythema6 reports
- application site pain6 reports
- pruritus6 reports
- second primary malignancy6 reports
- application site pruritus5 reports
Read these as a signal, not a rate. A report does not mean mechlorethamine caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved August 25, 2026.
Related calculators
Frequently asked questions
What is Valchlor?
VALCHLOR is a topical product that contains mechlorethamine HCl, an alkylating drug. Mechlorethamine HCl is a white to off white solid that is very soluble in water and methanol, partially soluble in acetone, and generally not soluble in organic solvents.
Can you take mechlorethamine with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run mechlorethamine against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is mechlorethamine sold under?
We track 2 mechlorethamine-containing products in the U.S.: Mustargen and Valchlor. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does mechlorethamine come in?
Across the brands we track, mechlorethamine is currently marketed as injectable and topical, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic mechlorethamine?
We do not currently list a generic-labelled mechlorethamine product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Mechlorethamine: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/mechlorethamine
- MLA
- “Mechlorethamine: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/mechlorethamine.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for mechlorethamine on DailyMed (NIH) ↗.