Ketamine treats depression and anxiety differently than selective serotonin reuptake inhibitors (SSRIs) such as Prozac. By blocking N-methyl-d-aspartic acid (NMDA) receptors, ketamine facilitates neuroplasticity, which is the brain’s ability to heal and form new connections. The effects of ketamine on the brain can be rapid and profound, relieving depression and helping to create healthier thought patterns.