Skip to Content
How to talk to a doctor about advanced ovarian cancer >>

Mechlorethamine (Topical)

Pronunciation

(me klor ETH a meen)

Index Terms

  • Mechlorethamine HCl (Topical)
  • Mechlorethamine Topical Gel

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Gel, External:

Valchlor: 0.016% (60 g) [contains edetate disodium, isopropyl alcohol, menthol, propylene glycol]

Brand Names: U.S.

  • Valchlor

Pharmacologic Category

  • Antineoplastic Agent, Alkylating Agent
  • Antineoplastic Agent, Alkylating Agent (Nitrogen Mustard)

Pharmacology

Mechlorethamine is a nitrogen mustard alkylating agent which forms inter- and intra-strand DNA cross-links, resulting in inhibition of DNA synthesis. Topical application allows for skin-directed treatment while minimizing systemic nitrogen mustard exposure (Lessin, 2013).

Absorption

Topical: None detected (Lessin, 2013)

Distribution

Topical: No detectable systemic exposure in a clinical study (Lessin, 2013)

Use: Labeled Indications

Cutaneous T-cell lymphoma: Topical treatment of stage IA and IB mycosis fungoides-type cutaneous T-cell lymphoma in patients who have received prior skin-directed therapy

Contraindications

Known severe hypersensitivity to mechlorethamine or any component of the formulation

Dosing: Adult

Cutaneous T-cell lymphoma (mycosis fungoides-type): Topical: Apply a thin film once daily to affected areas of skin

Note: Concurrent use of topical or systemic corticosteroids was not allowed in the clinical study (Lessin, 2013).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Renal Impairment

No dosage adjustment provided in the manufacturer’s labeling; however, based on the lack of systemic exposure, dosage adjustment is likely not necessary.

Dosing: Hepatic Impairment

No dosage adjustment provided in the manufacturer’s labeling; however, based on the lack of systemic exposure, dosage adjustment is likely not necessary.

Dosing: Adjustment for Toxicity

Skin ulceration (any grade), blistering, or dermatitis (moderately severe-to-severe): Withhold treatment; upon improvement, may reinitiate treatment with a reduced frequency of once every 3 days; if every 3-day application is tolerated for at least 1 week, may increase to every other day for at least 1 week, then (if tolerated) may increase to once daily.

Reconstitution

Hazardous agent – use appropriate precautions for handling and disposal (NIOSH 2014 [group 1]).

Administration

Apply a thin film topically to affected area. Apply immediately (or within 30 minutes) after removal from refrigerator; return to refrigerator promptly after each use. Apply to completely dry skin at least 4 hours before or 30 minutes after showering/washing. Allow treated area(s) to dry for 5-10 minutes after application before covering with clothing. May apply emollients (moisturizers) to treated area 2 hours before or 2 hours after mechlorethamine application. Do not use occlusive dressings over treatment areas. Avoid fire, flame, and smoking until mechlorethamine has dried.

Hazardous agent; use appropriate precautions for handling and disposal (NIOSH 2014 [group 1]). Caregivers should wear nitrile gloves when applying to patients. Wash hands thoroughly with soap and water after handling/application. If accidental skin exposure occurs, wash thoroughly for at least 15 minutes with soap and water; remove any contaminated clothing.

Storage

Prior to dispensing, store in freezer at -25°C to -15°C (-13°F to 5°F). After dispensing, refrigerate at 2°C to 8°C (36°F to 46°F); apply immediately (or within 30 minutes) after removal from refrigerator; return to refrigerator promptly after each use. Discard unused product 60 days after opening.

Drug Interactions

There are no known significant interactions.

Adverse Reactions

>10%:

Dermatologic: Dermatitis (56%; moderately severe or severe: 23%), pruritus (20%), bacterial skin infection (11%)

Hematologic & oncologic: Hematologic abnormality (decreased hemoglobin, neutrophils, or platelets; 13%)

1% to 10%:

Dermatologic: Dermal ulcer (6%), skin hyperpigmentation (5%)

Hematologic & oncologic: Malignant neoplasm (nonmelanoma skin cancer; 2%)

Postmarketing and/or case reports (Limited to important or life-threatening): Anaphylaxis, hypersensitivity reaction

Warnings/Precautions

Concerns related to adverse effects:

• Accidental exposure: Eye exposure may result in pain, burning, inflammation, photophobia, and blurred vision. Blindness and severe anterior eye injury (irreversible) may occur. If exposure to eye(s) occurs, promptly irrigate for at least 15 minutes with copious amounts of water, normal saline, or balanced salt ophthalmic irrigating solution; obtain ophthalmology consultation. Exposure to mucous membranes may cause pain, redness, and ulceration; may be severe. If mucosal contact occurs, irrigate promptly for at least 15 minutes with copious amounts of water and obtain medical consultation.

• Dermatitis: Dermatitis commonly occurs; may be moderately severe or severe. Monitor for redness, swelling, itching, blistering, ulceration, and secondary skin infections. Facial, genitalia, anus and intertriginous skin areas are at increased risk for dermatitis. Dermatitis may require dosage reduction.

• Secondary exposure: Avoid direct contact with mechlorethamine (other than intended treatment areas for the patient). Secondary exposure risks include dermatitis, mucosal injury, and secondary malignancies. To prevent secondary exposure, follow recommended application procedures.

• Secondary malignancy: In a clinical study, non-melanoma skin cancers developed during or within 1 year following treatment. Some instances occurred in patients who had received previous treatments that were associated with non-melanoma skin cancer. Monitor for non-melanoma skin cancers during and following treatment; may occur anywhere on the skin, including untreated areas.

Special handling:

• Hazardous agent – use appropriate precautions for handling and disposal (NIOSH 2014 [group 1]). Caregivers should wear nitrile gloves when applying to patients. Wash hands thoroughly with soap and water after handling/application. If accidental skin exposure occurs, wash thoroughly for at least 15 minutes with soap and water; remove any contaminated clothing.

Other warnings/precautions:

• Flammable gel: Mechlorethamine gel contains alcohol and is flammable; follow recommended application procedures and avoid fire, flame, and smoking until mechlorethamine has dried.

Monitoring Parameters

Monitor for dermatologic toxicity (skin ulcers, blistering, dermatitis, secondary skin infections) and signs/symptoms of non-melanoma skin cancer.

Pregnancy Risk Factor

D

Pregnancy Considerations

Adverse events have been observed in animal reproduction studies. There have been case reports of teratogenic events following systemic use in humans. Pregnancy should be avoided if therapy is needed.

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience itching or skin discoloration. Have patient report immediately to prescriber skin sores, blisters, redness, edema, signs of skin infection, skin ulcers, or skin growths (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

Hide