Morning dosing of once-daily glaucoma medication is more convenient and may lead to greater adherence than evening dosing.

PURPOSE: To determine if adherence and convenience of once-daily glaucoma medication is greater in the morning or the evening. DESIGN: Prospective, randomized crossover treatment trial. PATIENTS AND METHODS: Thirty patients newly diagnosed with glaucoma or ocular hypertension requiring intraocular pressure (IOP) reduction were started on travoprost eye drops and randomized to either morning or evening administration for 1 month. They were then crossed over to the opposite dosing schedule for the following month. Adherence was monitored using an automated dosing aid. MAIN OUTCOME MEASURES: Adherence was compared between morning versus evening dosing and first versus second month dosing. Demographic characteristics were obtained, treatment effect was measured, and patients completed a post-study questionnaire regarding the convenience of the 2 dosing regimens. RESULTS: Patient adherence overall was good (89.3%). There was no statistically significant difference (P=0.07) in adherence between morning dosing (90.9%) and evening dosing (87.3%). Adherence in the first month (91.7%) was superior to the second month (86.5%). There was no significant difference in IOP response between morning and evening dosing. Patients found morning dosing more convenient than evening dosing. CONCLUSIONS: Early adherence to treatment with a prostaglandin analogue is good, but patients prefer morning administration to evening administration. This may lead to greater adherence with morning administration, particularly among men. Adherence decreases from the first to second month after initiation of treatment. IOP response to this treatment is not significantly affected by morning versus evening administration.