A composition consisting of a semifluorinated alkane of the formula F(CF 2),(CH 2) mH, wherein n is an integer from the range of 3 to 8 and m is an integer from the range of 3 to 10, and optionally one or more further excipients may be used as a medicine in the treatment of keratoconjunctivitis sicca (dry eye) or a symptom or condition associated therewith