Imiquimod 5% cream for actinic keratosis.

Imiquimod 5% cream has been available since 1997 for the treatment of genital warts. Health Canada has expanded the indication to include actinic keratosis (AK). There are no trials comparing imiquimod 5% cream to standard AK therapy; placebo-controlled trials have shown an increased lesion clearance rate of 30% to 55% eight weeks post-treatment. Side effects include local skin reactions that can be severe and require discontinuation of treatment in 2% to 4% of patients. Imiquimod has shown a great potential for use in unapproved indications.