White tailed spiders
Medical Treatment Medical treatment is usually not required for white-tailed spider bites. The incidence of skin ulceration after bites by these spiders is unknown, but is likely to be extremely low. Local changes (typically redness, itch and pain) usually resolve within a few days. In cases of ongoing ulceration or necrosis, other causes, such as infection, circulatory problems etc., should be excluded.
Treatment of Necrotising Arachnidism There is as yet no definitive treatment for necrotising arachnidism. Those that have been tried include antibiotics, corticosteroids, hyperbaric oxygen therapy, surgical debridement +/- skin grafting (early or late) and (for loxoscelism) cytotoxics such as colchicine and cyclophosphamide. Antibiotics that have been used include dapsone (particularly in the United States), erythromycin and doxycycline, as well as penicillin , flucloxacillin and cephalosporins. None of the above treatments has been systematically trialled. Alternative treatments such as L-cysteine and aloe vera have also been used. There are anecdotal reports of success in healing ulcers, including ulcers thought to be related to spider bites, with hyperbaric oxygen therapy, but no organised trials have been conducted.