Section - Quick Takes

03. Serotonin Transporter Genetic Variation and Antidepressant Response and Tolerability: A Systematic Review and Meta-Analysis

Published on May 1, 2022 Expired on May 1, 2025

James Phelps, M.D.

Research Editor - Psychopharmacology Institute

Key Points

The long allele of the serotonin transporter gene (as opposed to the short one) is associated with better response to antidepressants in Caucasian patients.
No such association is observed in patients of Asian ancestry (perhaps because the long allele is much less common among them).
Does this have a major impact on deciding which antidepressant to use? That’s a different question.

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Text version

How long is your serotonin transporter gene or, perhaps the more relevant question is, how long is your patient’s serotonin transporter gene? The key question is, does it matter? Does serotonin transporter gene length, the long vs the short allele, predict response to serotonergic antidepressants? Are the genetic tests that purport to help you choose an antidepressant using gene length data appropriately?

Hi! Jim Phelps here for the Psychopharmacology Institute. Let’s look at the clinical value of knowing a patient’s serotonin transporter gene length. Let’s start with a review of data on the treatment of depression, where a recent review addresses the longstanding controversy about all these, and then we’ll move on to a new review of data regarding antidepressant response in conditions other than major depression.

Early studies showed that the long allele of the serotonin transporter gene, as opposed to the other shorter one, was associated with a

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04. Demographic and Clinical Characteristics of Patients Who Recommence Clozapine Following Therapy Interruptions

Learning Objectives:

After completing this activity, the learner will be able to:

Assess the efficacy and safety of mirtazapine for the treatment of agitation in patients with Alzheimer’s dementia.
Evaluate the efficacy of transcranial magnetic stimulation and transcranial direct current stimulation for the management of functional neurologic disorders.
Assess the impact of serotonin transporter gene length on antidepressant response and adverse effect rates.
Compare clozapine discontinuation rates, and reasons for doing so, among patients who later restarted vs never-again resumed clozapine.
Evaluate the extent to which caffeine can exacerbate anxiety symptoms among patients with panic disorder.

Original Release Date: May 1, 2022

Review and Re-release Date: March 1, 2024

Expiration Date: May 1, 2025

Expert: James Phelps, M.D.

Medical Editor: Melissa Mariano, M.D.

Relevant Financial Disclosures:

None of the faculty, planners, and reviewers for this educational activity have relevant financial relationships to disclose during the last 24 months with ineligible companies whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.

Contact Information: For questions regarding the content or access to this activity, contact us at support@psychopharmacologyinstitute.com

Instructions for Participation and Credit:

Participants must complete the activity online during the valid credit period that is noted above.

Follow these steps to earn CME credit:

View the required educational content provided on this course page.
Complete the Post Activity Evaluation for providing the necessary feedback for continuing accreditation purposes and for the development of future activities. NOTE: Completing the Post Activity Evaluation after the quiz is required to receive the earned credit.
Download your certificate.

Accreditation Statement

This activity has been planned and implemented in accordance with the accreditation requirements and policies of the Accreditation Council for Continuing Medical Education through the joint providership of Medical Academy LLC and the Psychopharmacology Institute. Medical Academy is accredited by the ACCME to provide continuing medical education for physicians.

Credit Designation Statement

Medical Academy designates this enduring activity for a maximum of 0.5 AMA PRA Category 1 credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.