Selective serotonin reuptake inhibitors (SSRIs)
Selective serotonin reuptake inhibitors raise serotonin levels by blocking its reuptake into nerve cells. They are first-line drugs for depression and are also used for anxiety disorders, OCD, and PTSD. Full benefit takes several weeks, and early side effects include nausea, trouble sleeping, and sexual dysfunction. Combining them with other serotonin-raising drugs can cause serotonin syndrome, and young people may have increased suicidal thoughts early in treatment.