In a prospective open clinical trial 20 patients with the diagnosis bacterial respiratory tract infection and underlying chronic obstructive lung disease were treated for 13 to 17 days with 200 mg cefixime b. i. d. 14 of 16 evaluable patients were treated successfully. In one patient the clinical symptoms remained unchanged and in another patient cefixime treatment failed. Ten of the 16 evaluable patients showed a positive baseline culture. In nine of these patients the initially isolated pathogens could be eliminated. In one patient, in whom cefixime therapy failed, change of pathogens was noticed after the end of treatment. Four of the 20 patients treated with cefixime reported side effects (gastritis, three; fungal dermatitis, one). In the patient with fungal dermatitis cefixime therapy was stopped.