Side Effect Profiles of Selective Serotonin Reuptake Inhibitors: A Cross-Sectional Study in a Naturalistic Setting

Background: Side effects of selective serotonin reuptake inhibitors (SSRIs), the most commonly used antidepressants, are usually underreported in clinical trials. Systematic evaluation of side effects associated with SSRIs with structured instruments in a naturalistic setting is an important design to fully understand the side effect profile of various SSRIs. We examined the frequencies of the side effects induced by 3 commonly used SSRIs, sertraline, escitalopram, and fluoxetine, by using a self-rating instrument designed to measure the subjective symptoms of patients in a naturalistic treatment setting. Methods: The subjects were outpatients recruited from the psychiatry department of a tertiary care hospital. The subjects were aged ≥18 years; were diagnosed with depression, anxiety spectrum disorders, adjustment disorder, hypochondriasis, or impulse control disorder according to ICD-10 criteria; and were on SSRI monotherapy. The assessment instrument included 42 items and was devised using drug package insert data on the most commonly observed side effects of antidepressants released by the US Food and Drug Administration. Results: A total of 100 patients participated in the study. Among them, 70% were women. The most common diagnosis was depression (49%). Of the patients, 53% were taking sertraline, 38% escitalopram, and 8% fluoxetine. The common side effects reported by patients were flatulence (64%), somnolence (59%), memory impairment (51%), decreased concentration (50%), yawning (47%), fatigue (45%), dry mouth (45%), weight gain (45%), light headedness (43%), and sweating (38%). Patients treated with escitalopram had significantly higher incidence of headache, pruritus, memory impairment, decreased concentration, and dizziness. Patients treated with sertraline had significantly decreased appetite. Conclusions: The study results highlight the prevalence and pattern of side effect profiles of 3 commonly used SSRIs and provide baseline data for comparison with other similar studies.