Ingenol mebutate induces strong inflammation after a single application already. This must be taken into account when prescribing the drug, as mistakes in the application may results in severe side effects. Here, we report the case of a 72-year-old woman who applied ingenol mebutate on the cheekbones and developed a pronounced conjunctivitis, needing topical corticosteroids. The treatment was intended for the actinic keratosis she had on the chest, and the regimen of 2 consecutive once daily applications of ingenol mebutate at 500 µg/g had been prescribed as registered. The inadvertent application on the thin skin of the cheekbones led to a pronounced inflammation. With topical steroids followed by fusidic acid, both conjunctivitis and skin inflammation resolved within a few days. The skin showed erythema for a few weeks, but after 3 months, the patient presented a perfectly smooth skin and was very happy with the cosmetic outcome. This suggests that the cheekbones are a sensitive site for ingenol mebutate, but that intense inflammation should not scare physician or patient, as clinical remission with excellent healing can still be expected.