OBJECTIVES: To gain an understanding of the use of self-administered topical therapies for actinic keratosis exploring patients’ persistence and adherence behaviour. METHODS: The study was conducted as an online longitudinal questionnaire-based survey in the UK, France and Germany between October 2012 and May 2013, among AK patients diagnosed and recruited by a physician +/- one week from any topical therapy initiation. The study design consisted of a baseline questionnaire followed by up to 6 follow-up questionnaires, completed at fortnightly intervals to cover a full treatment course. Persistence was calculated as persistence % = (Actual days of use/Advised days of use) x 100 and Adherence as Adherence % = (Actual times of use/Advised times of use) x 100, both were calculated using thresholds of 100% and 80%. Logistic regression modelling (multivariate analysis) was also performed to investigate causes of non-adherence/persistence among the patients. RESULTS: Overall, 224 patients completed the baseline questionnaire. Over 50% of the sample were prescribed diclofenac sodium at baseline, the remaining patients had been prescribed any of imiquimode 5 % or 3,75%, fluorouracil, or fluorouracil + salicylicacid. Over the course of the study approximately 2/3 of the patients remained on the same therapy from baseline to the end of the study and 1/3 ceased therapy or switched at least once. The majority of cases occurred on instruction from a healthcare professional (HCP). Of those who ceased or switched therapy, 79-94% of patients being non-persistent to their prescribed treatment duration, however, over 90% of patients were reported to be adherent to application. Controlled for treatment, gender and quality of life, patients aged >60 years were significantly more adherent compared to patients aged <60 years. CONCLUSIONS: This study reports that 1/3 of topical AK patients switch or prematurely stop treatment suggesting that patients experience issues preventing completion of treatment course.