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Cantharidin (On the skin)

Cantharidin (kan-THER-e-den)

Treats molluscum contagiosum (molluscum bumps).

Brand Name(s):

Ycanth

When This Medicine Should Not Be Used:

How to Use This Medicine:

Liquid

• Use this medicine only on your skin. Rinse it off right away if it gets on a cut or scrape. Do not get the medicine in your eyes, nose, or mouth.
• A nurse or other trained health professional will give you this medicine.
• Do not apply topical steroids, creams, lotions, or sunscreen to the affected area.
• Allow the medicine to dry for up to 5 minutes. Do not touch or allow the treated area to come in contact with your mouth, nose, genitals, or eyes for at least 24 hours after application or until washing.
• Do not allow children to lick or bite the treated areas. Do not inhale vapors from the topical solution during treatment.
• Do not cover the treated area with a bandage unless directed by your doctor.
• This medicine is flammable. Avoid fire, flame, or smoking near lesions during and after treatment until it is washed off of your skin.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding.
• This medicine may cause the following problems:
  • Eye problems (if it gets into your eyes)
  • Skin reactions
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Changes in skin color, flushing, redness, swelling of the treated area

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024