An ulceration misdiagnosed as being due to a spider bite was treated with intravenous hydrogen peroxide; the patient died.
An ulcerated plaque appeared on the left arm of a previously healthy 37-year-old man and was attributed to a spider bite. It did not respond to outpatient and later surgical debridement and a 1-week course of cephalexin hydrochloride. The patient sought care from an alternative medicine practitioner and received weekly intravenous infusions of hydrogen peroxide for 3 months for progressive ulceration. A persistent fever and unusual choreiform movements started 2 weeks later and progressed over a month to multisystem failure with encephalopathy, pancytopenia, renal insufficiency, liver dysfunction, coagulopathy, and Staphylococcus aureus bacteremia resistant to methicillin sodium. He was transferred to our institution, where his clinical condition deteriorated despite intensive management in an intensive care unit.
Wetter DA, Davis MDP. Ulceration of the Arm Attributed to a Spider Bite and Treated With Intravenous Hydrogen Peroxide: A Cautionary Tale. Arch Dermatol. 2006;142(12):1650-1666. doi:10.1001/archderm.142.12.1658