Side effects of Aldara (imiquimod) on equine sarcoids are primarily local skin reactions, including marked inflammation, redness, swelling, oozing, and crust formation at the application site. The horse may experience pain during crust removal and sedation may be required. Other side effects can include changes in skin pigmentation (hypo- or hyperpigmentation), which can be irreversible, and a strong, sometimes painful, inflammatory response. ,
Common Local Side Effects
- Intense inflammation: Aldara creates a strong local inflammatory response, leading to significant redness, swelling, and a thick crust at the treated area.
- Crust formation: The skin at the treatment site may develop thick crusts.
- Oozing/Exudation: The inflamed skin may ooze or exude fluid.
- Pain and tenderness: While horses may tolerate cream application, removal of the thick crusts before treatment can be painful and may require sedation.
Other Potential Side Effects
- Pigment changes:The skin around the sarcoid may experience changes in color, either lighter (hypopigmentation) or darker (hyperpigmentation). These changes can be permanent.
- Increased risk with overuse:Using too much Aldara or applying it for too long can increase the risk of severe skin reactions.
- Systemic effects (less common in horses):While the primary effects are local, systemic side effects like flu-like symptoms or back pain are sometimes reported with imiquimod use in humans, though their prevalence in horses is less clear