 [ Symptoms ] what causes a person to become allergic to ibuprofen  i have used ibuprofen for years with no problems i was started on meloxicam and had an allergic reaction to it i took ibuprofen after this and had a reaction to it also [ Disease ] allergies are not something we are born with but rather a sensitivity that is acquired over time from repeated exposure there is really no logical reason why you developed a sensitivity to ibuprofen but you did you will need to avoid this drug and drugs in this class from now on assuming it was a true allergic reaction