A patient on linezolid for MRSA pneumonia develops serotonin syndrome after starting an SSRI. Which mechanism explains this interaction?

• A Linezolid inhibits serotonin reuptake
• B Linezolid inhibits CYP2D6
• C Linezolid causes serotonin release
• D Linezolid is a reversible MAO-A inhibitor ✓

Explanation

Linezolid is a weak, reversible monoamine oxidase D inhibitor. When combined with SSRIs, it increases synaptic serotonin, risking serotonin syndrome. It does not inhibit CYP2A6 or directly cause serotonin release. This interaction is a key safety concern with oxazolidinones.

Reference: Katzung: Basic & Clinical Pharmacology, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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