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Mechlorethamine Topical

Mechlorethamine Topical 

En Español (Spanish Version)

(mek" lor eth' a meen )

WHY is this medicine prescribed?

Mechlorethamine gel is used to treat early stage mycosis fungoides-type cutaneous T-cell lymphoma (CTCL; a cancer of the immune system that begins with skin rashes) in people who have received previous skin treatment. Mechlorethamine gel is in a class of medications called alkylating agents. It works by slowing or stopping the growth of cancer cells.

HOW should this medicine be used?

Topical mechlorethamine comes as a gel to apply to the skin. It is usually applied once a day. Apply mechlorethamine gel at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Apply mechlorethamine gel exactly as directed. Do not apply more or less of it or apply it more often than prescribed by your doctor.

Talk to your doctor about how you are feeling while you are using mechlorethamine gel. Your doctor may stop the medication for a time or tell you to apply mechlorethamine gel less often if you experience serious side effects.

Your skin must be completely dry when applying mechlorethamine gel. You should wait at least 30 minutes after washing or showering before applying mechlorethamine gel. After you apply the medication, do not wash or shower for at least 4 hours. Moisturizers may be applied at least 2 hours before or 2 hours after using mechlorethamine gel.

Apply mechlorethamine gel within 30 minutes after you take it out of the refrigerator. Return mechlorethamine gel to the refrigerator right after each use. It is important to store your medication properly so that it will work as expected. Talk with your pharmacist before using mechlorethamine gel that has been out of the refrigerator for more than 1 hour a day.

Apply a thin layer of mechlorethamine gel to affected skin. Let the treated area dry for 5 to 10 minutes before covering with clothing. Do not use air or water-tight bandages on the treated areas. Wash your hands well with soap and water after applying or touching mechlorethamine gel.

If a caregiver applies the medication to your skin, he or she must wear disposable nitrile gloves and wash hands well with soap and water after removing the gloves. If a caregiver accidentally comes in contact with mechlorethamine gel, he or she must immediately wash the exposed area thoroughly with soap and water for at least 15 minutes and remove any contaminated clothing.

Mechlorethamine gel should only be used on the skin. Keep mechlorethamine gel away from your eyes, nose, and mouth. If mechlorethamine gel gets in your eyes, it can cause eye pain, burning, swelling, redness, sensitivity to light, and blurred vision. It may also cause blindness and permanent injury to your eyes. If mechlorethamine gel gets in your eyes, rinse your eyes right away for at least 15 minutes with a large amount of water, saline, or an eye wash solution and get emergency medical help. If mechlorethamine gel gets in your nose or mouth it can cause pain, redness, and ulcers. Rinse the affected area right away for at least 15 minutes with a large amount of water and get emergency medical help. Before you start your treatment with mechlorethamine gel, talk with your healthcare provider about how to get medical help quickly if the gel gets in your eyes, nose, or mouth.

Mechlorethamine gel may catch fire. Stay away from any source of heat or open flame and do not smoke while you are applying the medication and until it is completely dry.

Mechlorethamine gel is not available in pharmacies. You can only get mechlorethamine gel through the mail from a specialty pharmacy. Ask your doctor if you have any questions about receiving your medication.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before using mechlorethamine gel,

  • tell your doctor and pharmacist if you are allergic to mechlorethamine, any other medications, or any of the ingredients in mechlorethamine gel. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you are age 65 years or older or if you have or have ever had any medical condition.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using mechlorethamine gel, call your doctor immediately. Mechlorethamine can harm the fetus.
  • you should know that you, your caregiver, or anyone who comes into contact with mechlorethamine gel may have a higher risk of developing certain types of skin cancer. These skin cancers may occur anywhere on your skin, even areas that were not directly treated with mechlorethamine gel. Your doctor will check your skin for skin cancers during and after your treatment with mechlorethamine gel. Call your doctor right away if you notice any new skin changes or growths.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take a dose?

Apply the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not apply extra gel to make up for a missed dose.

What SIDE EFFECTS can this medicine cause?

Mechlorethamine gel may cause side effects. Tell your doctor if this symptom is severe or does not go away:

  • skin darkening

Some side effects can be serious. If you experience any of these symptoms, stop using mechlorethamine gel and call your doctor immediately or get emergency medical treatment:

  • skin redness, swelling, itching, blisters, or ulcers especially on the face, genital area, anus, or skin folds

• hives

  • difficulty breathing or swallowing

Mechlorethamine gel may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the original box, tightly closed, and out of reach of children. Store mechlorethamine gel in the refrigerator away from any food. Throw away any mechlorethamine gel that is not used after 60 days.

Unused mechlorethamine gel, empty tubes, and used application gloves should be thrown away safely in the trash out of the reach of children and pets.

What should I do in case of OVERDOSE?

If someone swallows mechlorethamine gel, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to mechlorethamine gel.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand Names

  • Valchlor®

Other Names

  • Nitrogen mustard

Medication Information

The information contained in this tool is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

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