A nationwide population study of trazodone use in urology patients

Erectile dysfunction (ED) has been a prevalent disease worldwide. The mainstay of treatment for ED focused on oral medications such as phosphodiesterase-5 (PDE-5) inhibitors or other medical aids with variable acceptance. Trazodone is a second-generation antidepressant approved by the U.S. Food and Drug Administration in 1981. Some evidence has suggested that trazodone may be helpful in improving ED, especially for problems dealing with male arousal. Although controversial, trazodone can sometimes be used for ED as an off-label medication for urological patients. By using a nationwide health insurance database, we attempted to estimate and thereafter analyze the existence and extent of off-label use of trazodone for ED in Taiwan.

The 1/500 randomly sampled outpatient visits dataset and the 1/1 million randomly selected dataset issued in 2000 in the National Health Insurance Research Database were used to estimate the total number of visits and the urological visits involving trazodone prescriptions. The refill rate, patient age at first prescription, and the diagnoses assigned to the prescription visits were also gathered and analyzed.

The prescription visits in urological clinics consisted exclusively of male patients (99.0 ± 1.3%, p < 0.001). The use of trazodone was more prevalent and regular among the elderly (p < 0.001), which happens to parallel the trend of incidence rates of ED. Starting in 1998, the prescription rate for trazodone increased rapidly, but then slowed, equalized, and topped out in 2003. One of the reasons for this marked change in prescriptions rates in Taiwan may be the increased awareness of ED as a treatable disease under the promotion and marketing of three PDE-5 inhibitors. ED-related diagnoses assigned to the prescription visits accounted for 55% of total visits, whereas anxiety/depression-associated diagnoses were the bases of less than 13%, and those attributed to insomnia accounted for 2.3% of visits.

Despite the fact that trazodone was not officially approved for patients with urological conditions, this medication has been used as an ED treatment in Taiwan at least since 1997; the prescriptions of trazodone were more prevalent among the elderly, and this trend increased, then evened out, and eventually reached its maximum point in 2003, correlating with the introduction of PDE-5 inhibitors.