The aim of this study is to investigate the effectiveness and practicality of the newly proposed guidance to take hypnotics 7 h before one’s usual wake-up time, compared to the conventional guidance to do so 30 min before bedtime. Subjects with primary insomnia who were not satisfied with their hypnotics were included between November 2014 and October 2015. Participants were instructed to take their own sleeping pills 7 h before their usual wake-up times, and sleep-related time variables and symptom questionnaires were assessed at baseline and after 2 weeks. Among 32 subjects, 23 patients were successfully followed up. Adhering to the said 7-h instruction, 73.9 % (n = 17) were satisfied with their sleeping pills. Mean hypnotics administration time was significantly delayed from 9:32 p.m. ± 0:58 to 10:55 p.m. ± 0:46 (p < 0.001), duration from pills to wake-up time (PTW) was shortened from 9.0 ± 1.1 to 7.1 ± 0.8 h (p < 0.001), and sleep latency (p = 0.023) was significantly shortened. Scores of ISI and PSQI significantly improved (p < 0.001), and the improvements of ISI and PSQI were positively correlated with the shortened sleep latency (r = 0.49, p < 0.05) and PTW (r = 0.54, p < 0.05), respectively. Advising patients to take hypnotics about 7 h before their usual wake-up time could increase the level of satisfaction with their original medication as is. In incorporating concepts of cognitive-behavioral therapy, this recommendation may serve as a simple but considerably useful guidance on the proper timing for taking prescribed sleeping pills.