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Imiquimod topical cream (Aldara, Beselna, Zyclara®) is an immune response modifier. It is used to treat certain types of skin growths including actinic keratoses (flat, scaly growths) and superficial basal cell carcinoma. It is available by prescription only. In horses imiquimod is primarily used to treat sarcoids and aural plaques.

Imiquimod stimulates the horse’s own immune system to fight the tumor, through inflammation.

Imiquimod is applied topically to an appropriate skin growth. If a tumor is very large or thick, it may need to be debulked (reduced in size) first with surgery.

This Treatment Might be used for a horse exhibiting these signsRelated Observations

Know Related Treatments

Consider Potential Side Effects & Complications

Local inflammation, swelling, pain and redness. These are signs that it is working. Scarring or hair loss at the tumor site may result.

Is It working? Timeframe for effect

Imiquimod is usually applied 2-3 times per week for 2-3 months. If there is no change in the appearance of the tumor or aural plaques after several months, the treatment may not be working.

Questions To Ask My Vet

  • For the particular tumor type, what is the chance for recurrence?

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Author: Doug Thal DVM Dipl. ABVP


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