Development of severe serotonin syndrome from acute ingestion of vilazodone without co-ingestion

Vilazodone is a selective serotonin reuptake inhibitor (SSRI) that was introduced to the market in 2011. It has a novel mechanism combining serotonin reuptake and partial agonism of 5HT-1 receptors. It has gained popularity in treating first generation SSRI-resistant depression. There has been little description in the literature of adult overdose. We are describing a 21-year-old female with an intentional overdose of 400 mg of vilazodone. This patient progressively developed worsening serotonin syndrome, which was resistant to aggressive benzodiazepine administration. The patient required sedation with propofol and phenobarbital to control serotonin syndrome. Patient required continued sedation for 36 h post-ingestion, with subsequent extubation and return to normal mental status. We detail an atypical case of a novel SSRI overdose with the treatment regimen used.