Carolinas Research Day 2021

Clinical Case-Based Studies

14 Introducing Two New Toxidromes: Antipsychotics and Atypical Antidepressants

Mya Lor OMS-IV, Erica Rubin OMS-IV, Hanna S. Sahhar, MD, FAAP, FACOP

Edward Via College of Osteopathic Medicine-Carolinas

Introduction: Typical and atypical antipsychotic medications have been available since the 1950s and 1970s, respectively, and have been approved to treat psychiatric and several mood disorders. Atypical antidepressants were designed to more effectively treat major depressive disorder. The use of these medications has become more prevalent leading to abuse and overdose. The two case reports highlight the toxicities of antipsychotics and atypical antidepressants and introduce two new toxidromes. Case one is a 17-year-old male with a past medical history of seizures, anxiety, and asthma presented to the emergency department (ED) with altered mental status. The patient was suspected of ingesting a large dose of an atypical antipsychotic medication due to his initial presentation of seizure, central nervous system depression, miosis, hypotension, tachycardia, and acute dystonia that was initially mistaken as decerebrate posturing. Within two days, hyperthermia was evident, and an electrocardiogram (EKG) showed prolongation of QTc interval. We can establish a

distinguished group of initial signs and symptoms associated with an exposure to a dangerous level of antipsychotic using the medications' affinity to certain receptors. Similar to our patient’s initial presentation, an antipsychotic toxidrome would present with hypotension with reflex tachycardia due to the inhibition of alpha-adrenergic receptors. Miosis of the pupils may also be observed due to an unopposed parasympathetic system because of the alpha-adrenergic receptor blockade. Antipsychotics also have a high affinity for dopamine receptors that can lead to extrapyramidal symptoms and neuroleptic malignant syndrome. Case two is a 13-year-old female with no significant medical history presented to the ED with seizure activity after intentionally ingesting 15 tablets of Bupropion. Physical examination was notable for injected conjunctiva, equal, round, and reactive pupils at 3 mm bilaterally, tachycardia, skin unremarkable, confusion, and delirium. Within three days, the patient recovered fully and was admitted to an

adolescent psychiatric unit for further evaluation. Like our patient’s initial presentation, an atypical antidepressant toxidrome may present with seizure activity due to inhibition of the reuptake of dopamine at the presynaptic cleft. Tachycardia can also be observed due to the inhibition of the norepinephrine reuptake. Serotonin syndrome may also be seen due to a variety of atypical antidepressants acting on the serotonin receptors. Signs and symptoms of antipsychotic and atypical antidepressant overdoses have historically been established, but they have never been introduced as toxidromes before. Toxidromes are medical emergencies that require immediate attention and treatment, but it can be challenging to recognize. Therefore, we propose two new toxidromes with defined characteristics to help healthcare providers identify and treat these toxidromes efficiently and effectively.

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