Introduction: During the COVID-19 pandemic, drug repurposing attempts increased due to limited therapeutic options in the setting of a high morbidity illness. Drug repurposing may also be utilized by those looking for alternative treatment modalities when faced with new medical illnesses. This case report demonstrates the danger of ivermectin use outside of its typical indications.
Case Report: A 69-year-old female presented to a hospital in Milwaukee, Wisconsin, United States of America with altered mental status. She was difficult to awake from sleep by her family. She had a recent diagnosis of metastatic breast cancer. Her initial evaluation including cerebral imaging and infectious assessment did not reveal an etiology for her encephalopathy. She was admitted to the hospital, and during her continued neurologic evaluation she made a gradual recovery. It was revealed by the patient and her family that she had been taking daily ivermectin as an attempted cancer treatment.
Discussion: Ivermectin is used as a deworming agent in veterinary medicine. Ivermectin potentiates gamma-aminobutyric acid (GABA)-gated currents. This explains its clinical effects of central nervous system depression. Treatment of ivermectin toxicity involves symptomatic and supportive care with gastrointestinal decontamination with activated charcoal if the ingestion occurs within 1 to 2 hours.
Conclusion: The undifferentiated encephalopathic patient often requires a broad laboratory and imaging evaluation. As in this case, taking a thorough history of present illness revealed ivermectin associated neurotoxicity as her final diagnosis. Emergency clinicians must be vigilant of this possible diagnosis especially with increasing attempts at drug repurposing.