Neurotoxicity and PRES after severe citalopram intoxication in a 12-months-old baby

Citalopram intoxications can lead to Serotonin Syndrome (SS) development, characterized by altered mental status, seizures, autonomic instability, hyperthermia and extrapyramidal signs. We review the literature about pediatric acute citalopram intoxications, and we report a case of severe SS in an infant associated to Posterior Reversible Encephalopathy Syndrome (PRES) treated with cyproheptadine as an antidote. An adequate12-month-old girl displayed a sudden global neurological regression with hypotonia, prolonged occipital seizures, right hemiparesis and a progressive wakefulness reduction associated with blindness. Plasmatic concentration of citalopram was equal to 3225 ng/mL (50-110 ng/mL). MRI revealed a transient bilateral caudate and putamen hyperintensity, associated to an occipital cortical and subcortical hyperintensity. She was treated with IV cyproheptadine with progressive benefit in few days. Only 4 children with citalopram intoxication are previously described with neurological involvement. Pediatric citalopram intoxication could cause SS leading to PRES, and cyproheptadine could be used with benefit.