A study of the association between patterns of eye drop prescription and medication usage in glaucoma subjects.

Purpose: To investigate the association between patterns of eye drop prescription and medication usage in patients with glaucoma.
Patients and Methods: Sixty-seven Japanese patients with glaucoma who were prescribed topical antiglaucoma medications including a prostaglandin analogue bilaterally for >6 months at Nayoro City General Hospital, Nayoro, Japan, were included in the study. A self-administered, 5-item patient questionnaire was administered to determine how patients routinely use medications, including the method of eye drop administration, number of eye drops per instillation, accuracy of eye drop placement, weekly frequency of eye drop application, and their awareness of local side effects. The number of prostaglandin analogue bottles prescribed monthly was compared in each factor.
Results: The mean patient age was 74.4±10.0 years (range, 52 to 95 y; 39 women, 28 men). The mean duration of glaucoma treatment was 4.2±3.2 years (range, 0.7 to 10.6 y). Patients who placed the eye drops outside the eye were prescribed significantly more bottles monthly (P=0.008). The other factors had no significant effect on the number of bottles prescribed monthly.
Conclusions: Patients with glaucoma who used eye drops incorrectly were routinely prescribed additional bottles of eye drops. Ophthalmologists should determine whether patients who request an unusual number of eye drops are using the eye drops correctly.