Wart Pen (Cantharidin) Treatment Guide walkthrough.
Compounded cantharidin (Wart Pen) is a topical treatment for warts and molluscum applied in-office or, in some prescriptions, at home. It causes a blistering response that lifts the wart over several days.
Step by step.
- 01
Read the prescription
Confirm whether your prescription is for at-home application or in-office only. Cantharidin is potent — follow the label exactly.
- 02
Clean the area
Wash the wart and surrounding skin with soap and water. Dry thoroughly.
- 03
Apply with the pen
Twist the cap to expose the applicator. Touch the tip to the wart only — do not get cantharidin on surrounding skin. One small drop is typically enough.
- 04
Cover (if instructed)
Some prescriptions ask you to cover with a bandage for 4-6 hours. Others ask you to leave open. Follow your label.
- 05
Wash off and watch
After the prescribed contact time, wash the area with soap and water. Expect a small blister to form over 24-48 hours, which will lift the wart over the following days.
Notes
- Severe pain, spreading redness, or signs of infection — call your prescriber.
- Don't apply to face, genital areas, or near the eyes unless specifically prescribed.
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