A 52-year-old man with MDD has been on sertraline 100 mg daily for 8 weeks with minimal improvement in depressed mood and anhedonia. He denies side effects and is adherent to medication. There is no suicidal ideation or psychotic features. What is the most appropriate next step in management?

Explanation

## Management of Partial Response to SSRI **Key Point:** After 8 weeks on an adequate SSRI dose (sertraline 100 mg is standard but not maximum), partial or non-response warrants dose escalation before switching or augmentation. The standard approach is to optimize the current agent first. ### Treatment-Resistant Depression (TRD) Definition **High-Yield:** TRD is defined as failure to achieve remission after **≥2 adequate trials** of antidepressants at **therapeutic doses for ≥4–6 weeks each**. This patient has completed only 1 trial; therefore, he does not yet meet TRD criteria. ### Stepwise Algorithm for SSRI Non-Response ```mermaid flowchart TD A[SSRI at standard dose for 4-6 weeks]:::outcome --> B{Response?}:::decision B -->|Yes| C[Continue, monitor for relapse]:::action B -->|No| D{Adequate dose reached?}:::decision D -->|No| E[Increase to maximum tolerated dose]:::action D -->|Yes| F[Reassess at 8-10 weeks]:::decision E --> F F -->|Still no response| G[Switch to different class OR augmentation]:::action F -->|Partial response| H[Consider augmentation]:::action G --> I[Document as TRD after 2 failed trials]:::outcome ``` ### Dose Escalation Strategy for Sertraline | Dose | Indication | Timeline | |------|-----------|----------| | 50 mg | Starting dose | Week 1 | | 100 mg | Standard therapeutic dose | Week 2–4 | | 150–200 mg | Inadequate response at 100 mg | Week 4–8 | | 200 mg | Maximum recommended dose | Week 8+ | **Clinical Pearl:** Sertraline 100 mg is considered a "standard" dose but not the maximum. Many patients require 150–200 mg for full response. Dose escalation should occur at 4-week intervals with reassessment. ### Rationale for Dose Increase 1. **Pharmacokinetics:** Sertraline shows dose-dependent response; higher doses achieve greater serotonin transporter occupancy. 2. **Timeline:** 8 weeks is adequate for initial assessment, but dose optimization may extend response time to 10–12 weeks. 3. **Safety:** No side effects reported; dose escalation is safe and appropriate. 4. **Cost-effectiveness:** Optimizing monotherapy is cheaper and simpler than switching or augmentation. **Mnemonic:** **DOSE FIRST** = **D**on't switch prematurely, **O**ptimize current agent, **S**tep up gradually, **E**valuate at 4-week intervals; **F**ull response takes 10–12 weeks, **I**ncrement by 25–50 mg, **R**eassess systematically, **S**witch only after 2 failed trials, **T**reat-resistant only then