Imiquimod is a prescription-only medication that is applied to the skin for the treatment of a variety of skin conditions, including the following:
- actinic keratoses (AKs), a precancerous skin growth that results from excessive sun exposure.
- basal cell carcinoma (a type of skin cancer)
- genital warts caused by infection with the HPV virus
- other skin conditions
Brand names of imiquimod include Aldara® and Zyclara®. Imiquimod is also available as a generic formulation.
How Does Imiquimod Work?
Imiquimod is categorized as an immune response modifier because it increases the activity of the body’s own immune system to identify and eliminate abnormal skin lesion. It is thought to lead to an increased levels of interferon and similar immune system signals in the skin that attack abnormal cells, viruses, and cancerous cells.
It is not known exactly how imiquimod cream works to treat actinic keratoses or superficial basal cell carcinoma.
Imiquimod cream does not cure warts, and new warts may appear during treatment. It is not known whether imiquimod cream prevents the spread of warts to other people.
Imiquimod may be used in combination with other treatments for maximize efficacy. For instance, it may be used in combination with cryotherapy for the treatment of actinic keratoses, or with Mohs surgery in the treatment of basal cell carcinoma.
Imiquimod and Skin Inflammation
When used to treat actinic keratoses and skin cancers, imiquimod results in inflammation, which destroys the skin lesion. The degree of inflammation is quite variable from person to person, in part due to the type of skin lesion and in part due to genetic factors.
Once the inflammation has settled there is generally a good or excellent cosmetic result with little scarring.
When Is Imiquimod Prescribed?
Imiquimod is usually prescribed to treat the skin conditions listed above. Your doctor may prescribe this medication in particular circumstances based on the location of the skin lesion, medical history and response to past treatments.
Imiquimod is particularly useful on areas where surgery or other treatments may be difficult, complicated or otherwise undesirable, such as the face, genital area and lower legs.
How is Imiquimod Used?
A course of treatment with imiquimod usually ranges from 4 to 16 weeks. The duration of treatment depends on the condition being treated and formulation of imiquimod being used.
Some formulations are designed for daily use. Other formulations, such as Zyclara®, are formulated for daily use for 2 weeks, followed by a 2 week rest period, and then again for 2 more weeks of daily use.
Be sure to talk to your doctor about how to properly apply imiquimod and the prescribed duration of treatment.