537 - Parkinson's Patients may be at higher risk for the rare Serotonin Syndrome: A case report

66 year old female presented to the hospital after several days of confusion/agitation, nausea. tremors, tachycardia in the setting of recent medication changes within 3 weeks. She was started on selegiline and Flexeril recently. Due similar presentation between Parkinson’s and serotonin syndrome, it was difficult to distinguish. Both neurology and psychiatry were consulted. Neurology’s differentials included serotonin syndrome, polypharmacy, and deconditioning. Notable on exam was the symmetric hyperreflexia. They recommended to stop Selegiline. MRI brain and EEG were negative. MRI spine significant for multiple age indeterminate thoracic compression fractures. Psychiatry was also involved in safely restarting her home Lexapro. She was admitted to inpatient rehab for continued PT/OT/SL as she was min to mod A with most of her ADLS.

Discussions:

Parkinson’s disease is a complex neurologic disease that often requires several pharmacologic agents that target Neurotransmitters. Many with PD have comorbid depression. This itself can put patients at higher risk for rare complications such as serotonin syndrome. Neurologists are using levodopa and carbidopa and sometimes selegiline, an MAO-B inhibitor, to prolong the dopamine effects. There is little research about the efficacy of the addition of Selegiline in practice and this would benefit from further research.

Conclusions: This case highlights the clinical expertise needed to differentiate worsening PD itself from serotonin syndrome due to their similar symptomatology. It also encourages providers to be mindful of a potential heightened risk of serotonin syndrome due to polypharmacy.