Adverse effect	Risk	Associated medication	Time to onset	Evidence
Gastrointestinal bleeding	OR = 1.2 to 1.558–10; risk is higher with concurrent use of antiplatelet or nonsteroidal anti-inflammatory drug9	SSRIs and serotonin-norepinephrine reuptake inhibitors associated with increased risk9,10; mixed findings for TCAs8,10	Anytime during treatment9	Meta-analyses9,10 and cohort study8
Hepatotoxicity	0.5% to 3% will have asymptomatic mild elevation in transaminase levels11	Higher risk with TCAs and nefazodone; lower risk with SSRIs11,12	Within six months11	Literature review
Hyponatremia	0.5% to 12% in older adults13,14	OR = 3.3 (95% CI, 1.3 to 8.6) for SSRIs compared with other drug classes15	Within first month16	Case-control study
QT prolongation	Dose dependent (2012 boxed warning not to exceed doses of citalopram [Celexa] > 40 mg per day or > 20 mg per day in adults older than 60 years)17	Citalopram, escitalopram (Lexapro), and amitriptyline	Initiation (but typically dependent on the presence of coexisting risk factors)18	Cross-sectional retrospective studies
Sexual effects	Weighted mean incidence across observational studies = 40% (95% CI, 28.3 to 52.6)19	Decreased risk with bupropion (Wellbutrin); trend toward increased risk with escitalopram and paroxetine (Paxil)19	Within first week20	Meta-analysis
Suicidality	Age related; slightly increased risk (OR = 2.30; 95% CI, 1.04 to 5.09) for adults 18 to 24 years of age; neutral for adults 25 to 64 years of age; protective for adults 65 years and older (OR = 0.06; 95% CI, 0.01 to 0.58)21	Insufficient evidence to determine differences between second-generation antidepressants	Within one to two months of initiation or dose increase22	Meta-analysis