Abstract
Serotonin toxicity, an adverse consequence of elevated serotonin levels in the brain, poses a considerable threat to life. Antidepressants, frequently prescribed for various conditions in older adults, such as depression, anxiety, and sleep disturbances, significantly contribute to this risk. The elderly are particularly vulnerable due to multiple comorbidities, cognitive decline, medication interactions, polypharmacy, and chronic kidney disease. This case underscores the critical importance of considering serotonin syndrome as a potential diagnosis in patients using serotonin and norepinephrine reuptake inhibitors, especially within vulnerable populations. Here, we present the case of an 89-year-old female who presented with altered mental status and a hypertensive emergency. Following a thorough examination and exclusion of alternative causes of acute encephalopathy, serotonin syndrome induced by the use of venlafaxine and oxycodone was diagnosed.