Comparison of the Efficacy and Tolerability of Solaraze for 3 Versus 6 Months in Patients With Mild to Moderate Actinic Keratosis Located on the Face and Head

Inclusion Criteria: * Visible and histologically proven actinic keratosis * Prepared and able to give written informed consent * ≥ 18 -80 years of age * Prepared and comply with all study requirements, including the following: application of gel on the treatment area twice a day, 5 / 7 clinic visits during the prestudy, treatment, posttreatment, and follow-up period * Pre- and posttreatment biopsy for histological confirmation (of clearance) of actinic keratosis diagnosis Exclusion Criteria: * Data of clinically significant, unstable, cardiovascular or haematologic, hepatic, neurologic, renal, endocrine, collagen-vascular, or gastrointestinal abnormalities or diseases * Known allergies to any excipient in the study drug * Any dermatological disease and/or condition in the treatment or surrounding area (3 cm distances from treatment area) that may be exacerbated by treatment with diclofenac or cause difficulty with examination * Active chemical dependency or alcoholism, as assessed by the investigator * Currently participating in another clinical study or have completed another clinical study with an investigational drug within the past 30 days * Received topical treatment at the treatment area with imiquimod or 5-FU within a time period of 1 month * Invasive tumours within the treatment area, e.g. merkel cell carcinoma, squamous cell carcinoma, basal cell carcinoma, the latter is accepted if completely surgically removed