What patient and clinical characteristics are most strongly associated with severe outcomes in patients presenting with acute diphenhydramine poisoning?
According to the cited reference, acidemia, QRS prolongation (>120ms), and elevated anion gap are most strongly associated with severe outcomes in diphenhydramine toxicity. Acidemia was the factor most strongly associated with all severe outcomes, including seizure. Hyperthermia (temperature >105F) and acute kidney injury (creatinine >2) were associated with severe outcomes, but not when controlling for age, sex, and intentionality.
Hughes AR, Lin A, Hendrickson RG; Toxicology Investigator’s Consortium (ToxIC). Clinical and patient characteristics associated with severe outcome in diphenhydramine toxicity. Clin Toxicol (Phila). 2021 Oct;59(10):918-925. doi: 10.1080/15563650.2021.1891244. Epub 2021 Mar 5. PMID: 33666139.