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Cantharidin (Topical application)

Generic name: cantharidin [ kan-THER-e-den ]
Brand name: Ycanth
Drug class: Topical keratolytics

Medically reviewed by Drugs.com. Last updated on Aug 12, 2023.

Uses for cantharidin

Cantharidin topical solution is used to treat molluscum contagiosum (molluscum bumps).

This medicine is to be given only by or under the direct supervision of your doctor.

Before using cantharidin

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of cantharidin topical solution in children younger than 2 years of age. Safety and efficacy have not been established.

Geriatric

No information is available on the relationship of age to the effects of cantharidin topical solution in geriatric patients.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Proper use of cantharidin

A nurse or other trained health professional will give you this medicine in a medical facility. It is applied only on your skin every 3 weeks as needed. Do not get the medicine in your eyes, nose, or mouth.

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 come in contact with your mouth, nose, genital areas, 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 your doctor has told you to.

This medicine is flammable. Avoid fire, flame, or smoking near lesions during and after treatment until it is washed off of your skin.

Detailed Cantharidin topical dosage information

Precautions while using cantharidin

It is very important that your doctor check your progress closely to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

This medicine may cause eye problems if it gets into your eyes. Check with your doctor right away if you or your child has blurred vision or blue-green halos seen around objects, dry eyes, or sensitivity of the eyes to light.

Skin reactions may occur after treatment with this medicine. Check with your doctor right away if you have breakdown of the outer layer of skin, dry skin, lightening or darkening of the skin, or small fluid filled or non-fluid filled raised blisters on or around the treated areas. You may wash the treated area with soap and water 24 hours after application. Do not use a washcloth, abrasive material, or vigorous rubbing because it could be painful.

Side Effects of cantharidin

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

Incidence not known

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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

Cantharidin topical side effects (more detail)

Commonly used brand name(s)

In the U.S.

In Canada

Available Dosage Forms:

Therapeutic Class: Keratolytic

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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