Which pharmacological agent is considered first-line treatment for Obsessive-Compulsive Disorder?

Explanation

## First-Line Pharmacotherapy for OCD **Key Point:** SSRIs are the gold-standard first-line pharmacological treatment for OCD. They are effective, well-tolerated, and have the strongest evidence base in randomized controlled trials. ### Pharmacological Treatment Hierarchy | Agent Class | Role in OCD | Evidence | |-------------|------------|----------| | **SSRIs** | **First-line** | Strong RCT evidence; FDA-approved (fluoxetine, sertraline, paroxetine) | | **Clomipramine** | Alternative first-line | Tricyclic with serotonergic activity; effective but more side effects | | **Antipsychotics** | Augmentation only | Used with SSRIs if partial response; not monotherapy | | **Benzodiazepines** | Short-term adjunct only | For acute anxiety; not effective for core OCD symptoms; risk of dependence | ### Commonly Used SSRIs in OCD - **Fluoxetine** — 40–80 mg/day (FDA-approved for OCD) - **Sertraline** — 50–200 mg/day (FDA-approved for OCD) - **Paroxetine** — 40–60 mg/day (FDA-approved for OCD) - **Escitalopram** — 10–30 mg/day (off-label, but effective) **High-Yield:** Doses required for OCD are typically **higher than those used for depression**. Response may take 8–12 weeks, longer than in depression (4–6 weeks). **Mnemonic:** **SSRI-OCD** — SSRIs are the **Serotonin-Specific, Robust, Initial** choice for OCD. **Clinical Pearl:** If SSRIs fail, clomipramine (a tricyclic with strong serotonergic properties) is the next option. Antipsychotics (risperidone, aripiprazole) are used as **augmentation** to SSRIs in partial responders, not as monotherapy. [cite:Harrison 21e Ch 470; American Psychiatric Association Practice Guideline for OCD]