What is Cantharidin? How does it work in removing warts?

General Information about warts 

Warts are skin growths caused by viruses. Warts can grow on any part of the body. Their appearance depends primarily on their location. Although they don’t spread easily, wart viruses can be passed to others by direct contact, or indirectly in such places as locker rooms and public showers. They can also spread on the sameindividual by picking, scratching, etc. Warts are sometimes easy to live with, but they can be unsightly and become painful, especially on the feet. Warts will sometimes bleed if injured. 

How does it work? 

The normal action of these medications is to form a blister underneath the wart. This occurs within 24 hours of application. The blister formation kills the wart by cutting off its blood supply. Occasionally, there may be some blood in the blister fluid...don’t be alarmed at this. The blister may also be painful, inflamed and itch. Your physician will recommend appropriate medication. 

Treatment Progression & what you can expect 

As a general rule, you can expect the following: 

  • 4 HRS: Mild discomfort may occur. Control with bathing and medication. (Removing dressing) 
  • 24 HRS: Blistering, usually within 24 hours. 
  • 4 DAYS: Crusted blisters fall off leaving superficial erosions. Medication may be needed to control night time itching. 
  • 7 DAYS: Healed with temporary residual inflammation/redness. Any resistant lesions will be re-treated by your physician at your next appointment. Temporary loss of normal pigmentation often occurs, but no scarring. 


Your wart has been covered with a dressing to help the Cantharone Plus® penetrate. REMOVE DRESSING AFTER 4 HOURS. Remove dressing and then rinse with water or a mild cleanser. You can shower. After you dry off, protect the area with a loose dressing. Vaseline or Aquaphor can be applied to irritated or itchy lesions. 

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