eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2020-01-17 8 3 73 75 10.12691/ajmcr-8-3-2 AJMCR2020832 article Justina Ray 1 Abdullah Mahmood 1 Muhammad Dogar 1 Junjing Guo 1 Felix Nwamaghinna 1 Louis Salciccioli 1 Samy I. McFarlane Samy.mcfarlane@downstate.edu 1 Department of Medicine, SUNY-Downstate Health Science University, 450 Clarkson Avenue, Brooklyn, New York 11203, USA We present a case of simultaneous cardiotoxicity and stroke-like neurotoxicity in a patient treated with FOLFOX, a 5-Fluorouracil (5-FU)-containing chemotherapy regimen. Within hours of FOLFOX infusion, the patient began to exhibit signs and symptoms of myocardial ischemia and stroke mimic. Coronary vasoconstriction and vasospasm is a known mechanism of 5-FU-induced cardiotoxicity. 5-FU-induced neurotoxicity commonly presents as encephalopathy and is likely attributable to the accumulation of ammonia, a product of 5-FU metabolism. However, our patient presented with focal neurological signs and normal levels of ammonia. This suggests that 5-FU-induced vasospasm in the coronary arteries and cerebral vasculature is a likely cause of the simultaneous cardiac and neurological events we report here which have not been reported previously. Recognition of these toxicities as complications of 5-FU chemotherapy is crucial for the proper diagnosis and treatment of patients. http://pubs.sciepub.com/ajmcr/8/3/2/ajmcr-8-3-2.pdf FOLFOX 5-fluorouracil 5-FU chemotherapy cardiotoxicity neurotoxicity