Brintellix (vortioxetine) is an antidepressant used to treat major depressive disorder (MDD). Common side effects of Brintellix include nausea, constipation, vomiting, and sexual dysfunction.Antidepressants can raise the risk of suicidal thoughts among some users, especially among children, adolescents, and adults aged 18 to 24.he most commonly observed adverse reactions in MDD patients treated with BRINTELLIX in 6 to 8 week placebo-controlled studies (incidence ≥ 5% and at least twice the rate of placebo) were nausea, constipation and vomiting.