Selective Serotonin Reuptake Inhibitors (SSRI)

Selective Serotonin Reuptake Inhibitors (SSRI) are first-line agents for treatment of mood disorders and anxiety disorders. The exact agent chosen will vary depending on prescriber comfort and specific patient factors including gender, diagnosis, symptoms, and patient preference.

  • SSRIs increase serotonin (5-HT) by inhibiting the serotonin transporter (SERT) and decreasing reuptake into cells. This impacts the serotonin:receptor ratio. Homeostatic forces result in adjustments in serotonin throughout the body.
  • GI upset, headaches, dry mouth, sexual dysfunction, and weight gain may be common.
  • Long-term use of SSRIs is associated with an increased risk of falls and fractures that is unrelated to postural hypotension, fractures, and hyponatremia.[1]
  • SSRIs can inhibit platelet aggregation via altering platelet serotonin receptors.
  • This can increase the risk for gastrointestinal bleeding, and the risk may be doubled with concurrent use of nonsteroidal anti-inflammatory drugs (NSAIDs).
  • Use of acid-suppressing drugs such as proton pump inhibitors (PPIs) can reduce the risk of gastrointestinal (GI) bleeding.
  • There is a risk for increased suicidal behaviour and ideation for youths on antidepressants.
  • SSRI use late in pregnancy has been associated with an increased risk of persistent pulmonary hypertension (PPHN) of the newborn (risk is 3 in 1,000; compared to population risk of 2 in 1,000).[2]