The oral nonergot dopamine agonist pramipexole (Mirapex ER, and generics), which is FDA-approved for treatment of Parkinson's disease and restless legs syndrome, has been used off-label in patients with treatment-resistant depression (TRD). A double-blind, placebo-controlled trial of pramipexole augmentation in patients with unipolar TRD was recently published.

A selective serotonin reuptake inhibitor (SSRI) is generally used for initial treatment of major depressive disorder (MDD). A serotonin-norepinephrine reuptake inhibitor (SNRI), bupropion (Wellbutrin SR, and others), and mirtazapine (Remeron, and others) are reasonable alternatives. Improvement in symptoms can occur within the first two weeks of treatment with these drugs, but a substantial benefit may not be achieved for 4-8 weeks.

The FDA has approved an extended-release fixed-dose combination of dextromethorphan and bupropion (Auvelity – Axsome) for treatment of major depressive disorder (MDD) in adults.

Esketamine (Spravato – Janssen), an intranasal N-methyl-D-aspartate (NMDA) receptor antagonist that was previously approved by the FDA for treatmentresistant depression,1 has now been approved for treatment of depressive symptoms in adults with major depressive disorder (MDD) and acute suicidal ideation or behavior. Esketamine is the S-enantiomer of the anesthetic ketamine (Ketalar, and generics). It is the first drug to be approved for this indication. Most clinical trials of antidepressants have excluded patients with acute suicidal ideation.

Complete remission of symptoms is the goal of treatment for major depressive disorder; a partial response is associated with an increased risk of relapse. Improvement in symptoms can occur within the first two weeks of treatment with an antidepressant, but it may take 4-8 weeks to achieve a substantial benefit. Following successful treatment of a first major depressive episode, antidepressant treatment should be continued at the same dose for at least 4-9 months to consolidate recovery. In patients with recurrent depressive episodes, long-term maintenance treatment can reduce the risk of relapse.

The FDA has approved esketamine (Spravato – Janssen), an N-methyl-D-aspartate (NMDA) receptor antagonist, for intranasal treatment (in conjunction with an oral antidepressant) of adults with treatment-resistant depression (TRD). This is the first FDA approval for esketamine, which is the S-enantiomer of the intravenous anesthetic ketamine (Ketalar, and generics). In recent years, IV ketamine has been increasingly used (off-label) for treatment of TRD.