The United States Food and Drug Administration (FDA) has explicitly discouraged the use of ivermectin for the treatment of cancer outside of clinical trials. Nevertheless, patient self-administration persists, frequently influenced by information encountered online. Cases of ivermectin neurotoxicity in the oncology setting remain underreported despite growing off-label use driven by online misinformation. We present a case of severe neurotoxicity following unintentional high-dose self-administration of ivermectin as an off-label attempt to treat breast cancer. A 73-year-old female with metastatic breast cancer self-administered high doses of ivermectin based on information obtained online. She subsequently developed acute altered mental status, generalized seizures, and respiratory failure. Her clinical course was consistent with severe ivermectin-induced neurotoxicity, necessitating supportive management including intubation, mechanical ventilation, intravenous fluids, and anticonvulsant therapy. The patient demonstrated full neurological recovery to baseline within 48 hours. This case highlights the potential for life-threatening neurotoxicity associated with high-dose ivermectin use. Increasing online health misinformation has led to the self-administration of unproven therapies; therefore, clinicians should counsel patients on the risks of non-evidence-based treatments. A thorough exposure history is essential to identify uncommon causes and maintain vigilance for severe adverse reactions.

Patients with chronic liver disease are systematically excluded from acute myocardial infarction (AMI) trials, and prior real-world data rely on administrative coding alone. Whether ICD-coded liver disease and laboratory-defined liver fibrosis identify the same patients, and whether they predict the same outcomes, is unknown. We conducted a single-center retrospective cohort study of 1037 consecutive adults admitted with AMI (ICD-10 I21.x) to a tertiary New York center between November 2022 and December 2024. The primary exposure was ICD-defined advanced liver disease (cirrhosis, hepatic failure, or portal hypertension/decompensation; n = 102). The secondary, lab-based exposure was the Fibrosis-4 (FIB-4) index calculated from earliest admission AST, ALT, and platelet count (computable in 1031 patients, 99.4%), stratified as low (3.25). Co-primary outcomes were invasive management (diagnostic angiography, percutaneous coronary intervention, or coronary artery bypass grafting) and in-hospital mortality. Multivariable logistic regression adjusted for age, sex, diabetes, chronic kidney disease, heart failure, and ST-elevation; the trend across FIB-4 tiers was assessed with the Cochran–Armitage test. Denominators throughout (including the 168/909 occult-fibrosis estimate) use the full exposure group as denominator under a missing-as-not-exposed convention; the four no-LD and two advanced-LD patients with missing FIB-4 are counted as non-advanced fibrosis for this calculation. Patients with ICD-defined advanced liver disease received invasive management less often (12.7% vs. 50.4%; adjusted odds ratio [aOR] 0.17, 95% CI 0.09–0.32) and died in hospital more often (43.1% vs. 7.9%; aOR 8.22, 95% CI 5.02–13.46) than patients without coded liver disease. Outcomes worsened monotonically across FIB-4 tiers (mortality 4.4% → 9.2% → 27.5%; invasive management 55.2% → 45.6% → 33.5%; both p < 0.001 by Cochran–Armitage trend test). Critically, 168 of 909 patients with no coded liver disease (18.5%) had FIB-4 > 3.25, representing a substantial population of unrecognized advanced fibrosis missed by clinical coding. Coded liver disease identifies a small, severely affected subgroup with markedly lower rates of invasive management and 6- to 8-fold higher mortality after AMI. Routine FIB-4 calculation, a free, three-variable lab score, identifies a much larger population with occult advanced fibrosis and graded excess risk that ICD codes miss entirely. Pending prospective validation, FIB-4 may serve as a low-cost adjunct to bedside risk stratification in AMI care.