How long do I have to be on antidepressants?

The optimal length of time a patient should be on an antidepressant varies significantly based on factors such as age, diagnosis, response to treatment, and the chronicity of the symptoms.

Timeframe for Initial Response and Full Trial

• Onset of Therapeutic Effect: The therapeutic effect of many antidepressants, including Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs), Serotonin Antagonist and Reuptake Inhibitors (SARIs), Noradrenergic/Specific Serotonergic Antidepressants (NaSSAs), and nonselective cyclics (TCAs), is typically seen after 28 days. Some patients, however, may respond sooner.

• Lack of Early Improvement: A lack of early improvement (less than 20% reduction in symptoms scores) at 2–4 weeks after starting an antidepressant is strongly associated with nonresponse and nonremission at later time points.

• Full Trial Duration: For patients with Chronic Kidney Disease (CKD), a full trial of an antidepressant should last approximately 8–12 weeks, which is a longer period than the up to 8 weeks recommended for the general population, possibly due to slower symptom improvement in this group.

  
  

Recommendations for Continuation and Maintenance

Achieving full symptom remission is associated with a lower risk of relapse compared to achieving only a partial response.

• Children and Adolescents with Major Depression: Current recommendations suggest maintaining antidepressant treatment for 1 year in a depressed child who has achieved a good response, followed by discontinuing the medication at a time of relatively low stress.

• Children and Adolescents with Obsessive-Compulsive Disorder (OCD): For youth with more severe or multiple episodes of significant symptom exacerbation, treatment for more than a year is recommended.

• Adult Recovery: Recovery from a major depressive episode begins within 3 months for 40% of individuals and within 1 year for 80%.

• Persistent Depressive Disorder (Dysthymia): This disorder requires a depressed mood that occurs for most of the day, for more days than not, for at least 2 years (or at least 1 year for children and adolescents).

• Treatment-Resistant Depression (Esketamine): For patients responding to esketamine adjunctive therapy for treatment-resistant depression, clinical guidelines recommend that treatment be maintained for at least 12 months.

• Recurrence Risk: The most significant risk for relapse in depressed children and adolescents is in the 6 months to 1 year after discontinuing treatment.

  
  

Discontinuation and Tapering of Antidepressants

Antidepressants are not addictive but are associated with discontinuation symptoms upon cessation.

• General Tapering Guidance: Individuals on long-term treatment (more than 6 months) may benefit from a longer taper (e.g., more than 3 months).

• Duration to Avoid Discontinuation Syndrome: A discontinuation syndrome is unlikely if the treatment duration has been less than 4 weeks.

• Agent-Specific Tapering: The risk of discontinuation symptoms varies; it is reported most frequently with paroxetine and venlafaxine, and least with fluoxetine. Fluoxetine can be tapered more rapidly due to its prolonged half-life.