How do psychiatrists decide which antidepressants to use? For the purposes of this blog post by Memor Health’s Dr. Alex Brooks D.O., we will discuss a treatment algorithm for unipolar depression (without psychosis) in the outpatient setting.

An Antidepressant Algorithm For (Unipolar) Depression 

The first step in this process is the establishment of a correct diagnosis. The next few guiding principles revolve around a medication’s effectiveness and safety profile. There are also situations where the financial burden needs to be taken into account. Let’s also not forget to emphasize the use of other psychosocial interventions such as psychotherapy, exercise, and dietary considerations. Additionally, medication may not be the best option for some individuals.

Usually medication treatment for the above listed condition starts with a SSRI (selective serotonin reuptake inhibitor). The article cited below from the Harvard Review of Psychiatry suggests escitalopram and sertraline. This same article also mentions the option to initially use bupropion (a norepinephrine and dopamine reuptake inhibitor). Painstakingly, it can take up to six weeks to determine if this medication will be effective. This is referred to as an ‘adequate trial’. If the response is inadequate, and one would like to continue with medication trials, some options include switching medication and Augmentation Strategy:

Switching medication: 

  • From escitalopram/sertraline to bupropion (or vice versa)
  • To a SNRI (serotonin norepinephrine reuptake inhibitor)
  • To mirtazapine
  • There are many other options as well but are outside the scope of this brief discussion

Augmentation Strategy (add a second medication): 

  • -L-methylfolate
  • Fatty acids
  • bupropion
  • mirtazapine
  • an atypical antipsychotic such as aripiprazole or quetiapine
  • lithium
  • thyroid (T3) hormone
  • There are many other options as well but are outside the scope of this brief discussion

Once the pertinent information and options have been discussed, it is usually most helpful for the client to have a strong influence on the treatment trajectory. There are also many other considerations that could influence the direction such as avoidance of certain medication side effects, co-morbid psychiatric conditions, or co-morbid medical conditions. As always, a careful and well thought out decision between the client and psychiatric provider is always the best starting place for developing a treatment plan at any stage of the game.

DISCLAIMER: The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified physician or other health care provider. The information provided here is for informational purposes only.

Resources/Additional Information: 

Giakoumatos, C. I., & Osser, D. (2019). The Psychopharmacology Algorithm Project at the Harvard South Shore Program: An Update on Unipolar Nonpsychotic Depression. Harvard Review of Psychiatry, 27(1), 33-52.
Gertsik, L., Poland, R. E., Bresee, C., & Rapaport, M. H. (2012). Omega-3 fatty acid augmentation of citalopram treatment for patients with major depressive disorder. Journal of clinical psychopharmacology, 32(1), 61.
Papakostas, G. I., Cassiello, C. F., & Iovieno, N. (2012). Folates and S-adenosylmethionine for major depressive disorder. The Canadian Journal of Psychiatry, 57(7), 406-413.
Berman, R. M., Fava, M., Thase, M. E., Trivedi, M. H., Swanink, R., McQuade, R. D., … & Marcus, R. N. (2009). Aripiprazole augmentation in major depressive disorder: a double-blind, placebo-controlled study in patients with inadequate response to antidepressants. CNS spectrums, 14(4), 197-206.
Spielmans, G. I., Berman, M. I., Linardatos, E., Rosenlicht, N. Z., Perry, A., & Tsai, A. C. (2013). Adjunctive atypical antipsychotic treatment for major depressive disorder: a meta-analysis of depression, quality of life, and safety outcomes. PLoS medicine, 10(3), e1001403.
Fava, M., Rush, A. J., Trivedi, M. H., Nierenberg, A. A., Thase, M. E., Sackeim, H. A., … & Kupfer, D. J. (2003). Background and rationale for the sequenced treatment alternatives to relieve depression (STAR* D) study. Psychiatric Clinics of North America.
Carpenter, L. L., Yasmin, S., & Price, L. H. (2002). A double-blind, placebo-controlled study of antidepressant augementation with mirtazapine. Biological psychiatry, 51(2), 183-188.