80%) of sunscreens may contain octocrylene". [4] However, as a chemical sunscreen, “These very chemically reactive UV filters are well known for inducing allergic contact dermatitis as well as photoallergic contact dermatitis (PACD)” [2], "Octocrylene appears to be a strong allergen leading to contact dermatitis in children and mostly photoallergic contact dermatitis in adults". [2] Those who have had a history of photoallergic contact dermatitis should refrain from using octocrylene. After using ketoprofen, a nonsteroidal anti-inflammatory drug (NSAID), do not use octocrylene. There seems to be an adverse drug-chemical interaction between ketoprofen and octocrylene. "photoallergic contact dermatitis in adults with an often associated history of photoallergy from ketoprofen" [2], "He [the patient] had a history of cutaneous allergic reactions after topical use of ketoprofen". [3] Ketoprofen can therefore tentatively be used as an indicator for octocrylene sensitivity though the mechanism of interaction remains unknown. [3] "Photosensitization to ketoprofen leads, in many cases, to photocontact allergy to octocrylene; the mechanism of this reaction is unknown." [4] " /> 80%) of sunscreens may contain octocrylene". [4] However, as a chemical sunscreen, “These very chemically reactive UV filters are well known for inducing allergic contact dermatitis as well as photoallergic contact dermatitis (PACD)” [2], "Octocrylene appears to be a strong allergen leading to contact dermatitis in children and mostly photoallergic contact dermatitis in adults". [2] Those who have had a history of photoallergic contact dermatitis should refrain from using octocrylene. After using ketoprofen, a nonsteroidal anti-inflammatory drug (NSAID), do not use octocrylene. There seems to be an adverse drug-chemical interaction between ketoprofen and octocrylene. "photoallergic contact dermatitis in adults with an often associated history of photoallergy from ketoprofen" [2], "He [the patient] had a history of cutaneous allergic reactions after topical use of ketoprofen". [3] Ketoprofen can therefore tentatively be used as an indicator for octocrylene sensitivity though the mechanism of interaction remains unknown. [3] "Photosensitization to ketoprofen leads, in many cases, to photocontact allergy to octocrylene; the mechanism of this reaction is unknown." [4] " />