The investigators plan to treat 30 subjects. Each qualifying subject will have at least 3 hypertrophic AKs, defined as more than 3mm in thickness, on each dorsal hand. Cryotherapy will be standardized in all patients and for all treated lesions: 1-2 sprays, 5 seconds each, with a 5 second interval. All subjects will be treated with the same cryo-spray. Following cryotherapy, subjects will be randomized to treat either their right or left dorsal hand with ingenol mebutate gel. The decision to treat the right vs. the left hand will be chosen by chance, like flipping a coin. Neither the subject nor the study doctor will choose what arm receives the ingenol mebutate gel. The study doctor will not know which arm is treated with ingenol mebutate, so the subject should not reveal that information to him or her at any time during the study. Subjects will treat the randomized dorsal hand with ingenol mebutate 0.05% gel starting on the same day as the cryotherapy (Day 0). Subjects will utilize the once daily for two days regimen. Subjects will be followed on day 4 after their initial visit, day 8, day 15, day 29, and day 57, with a two day window period.