What are the next steps for a patient on Cymbalta (duloxetine) 120 mg for Generalized Anxiety Disorder (GAD) who also needs to treat Obsessive-Compulsive Disorder (OCD)?

Treatment for OCD in a Patient on Cymbalta 120 mg for GAD

For a patient currently on Cymbalta (duloxetine) 120 mg for GAD who also needs treatment for OCD, the recommended next step is to switch to an SSRI such as sertraline (starting at 50 mg/day and titrating up to 50-200 mg/day), as SSRIs are the first-line pharmacological treatment for OCD and require higher doses for OCD than for anxiety disorders. 1

Current Treatment Evaluation

Duloxetine (Cymbalta) is an effective treatment for GAD at doses of 60-120 mg daily 2, 3. While duloxetine has demonstrated efficacy in preventing relapse in GAD 4, it is important to note that:

• Duloxetine is not FDA-approved for OCD treatment
• SSRIs are specifically recommended as first-line pharmacological treatment for OCD 1
• Higher doses of SSRIs are typically required for OCD compared to depression or anxiety disorders 1

Treatment Algorithm for OCD with Comorbid GAD

Step 1: Medication Switch

• Switch from duloxetine to sertraline, which is a preferred SSRI for OCD treatment 1

  • Initial dose: 50 mg/day
  • Target dose range: 50-200 mg/day
  • Maximum dose: 200 mg/day
  • Mean effective dose in clinical trials: approximately 185 mg/day

• Cross-titration approach:

  • Gradually taper duloxetine while introducing sertraline
  • Monitor for discontinuation symptoms from duloxetine (commonly nausea and dizziness) 2

Step 2: Add Cognitive-Behavioral Therapy with Exposure and Response Prevention (CBT-ERP)

• CBT-ERP has larger effect sizes than pharmacological therapy alone (number needed to treat: 3 for CBT vs. 5 for SSRIs) 1
• Can be used in combination with medication for better outcomes

Step 3: Assessment of Response

• Continue treatment for at least 8-12 weeks at maximum tolerated dose to determine efficacy 1
• Monitor for:
  • Reduction in OCD symptoms
  • Maintenance of GAD symptom control
  • Side effects and tolerability

Step 4: If Inadequate Response

Consider augmentation strategies:

• Adding an antipsychotic (risperidone or aripiprazole) 1
• Adding glutamatergic agents (N-acetylcysteine, memantine) 1

Rationale for SSRI Switch

1. Evidence-based recommendation: The American College of Physicians and American College of Psychiatry both recommend SSRIs as first-line pharmacological treatment for OCD 1

2. Efficacy: SSRIs have demonstrated superior efficacy specifically for OCD compared to SNRIs like duloxetine

3. Comprehensive coverage: Sertraline is effective for both OCD and GAD, providing coverage for both conditions

Common Pitfalls to Avoid

1. Inadequate dosing: OCD typically requires higher SSRI doses than those used for depression or anxiety disorders 1

2. Premature discontinuation: Maintain treatment for 12-24 months after achieving remission 1

3. Failure to recognize partial response: Some patients may have residual symptoms requiring augmentation strategies

4. Insufficient psychological intervention: Combining medication with CBT-ERP provides superior outcomes compared to medication alone 1

5. Poor monitoring: Regular assessment of both OCD and GAD symptoms is essential to ensure neither condition worsens during treatment transition

By following this evidence-based approach, the patient can receive optimal treatment addressing both their OCD and GAD symptoms, with careful monitoring during the transition from duloxetine to sertraline.