The incidence of phototoxicity as a side effect of ciprofloxacin appears to be increased in patients with cystic fibrosis compared to the general population (approximately 2.4%). We used an interview‐based questionnaire to determine the incidence of such phototoxic skin reactions in cystic fibrosis patients. Results from 105 respondents revealed the incidence of ciprofloxacin‐induced phototoxicity in the adult cystic fibrosis population in Northern Ireland to be 48.4% with only 66% of the patients recalling being given sun care information beforehand. We concluded that the incidence of phototoxicity is increased in patients with cystic fibrosis and that it is important for all to receive good sun care information prior to taking ciprofloxacin given the high risk of developing phototoxic rash.