White-tailed spiders

White-tailed spiders are found in most areas of Australia and are common in urban dwellings. They are readily identifiable by their cylindrical body shape and the presence of a white or grey spot on the end on their abdomen. They are active hunters, preying on other types of spiders, and may be found roaming inside houses, especially in warmer weather. White-tailed spiders have been implicated in some cases of necrotising arachnidism (skin breakdown or ulceration following spider bites).

There is currently no antivenom or other specific treatment for white-tailed spider bite.

• Most cases of witnessed white-tailed spider bites do not develop ongoing ulceration, although blisters and redness are common.
• A small number of witnessed white-tailed spider bite cases have been associated with skin ulceration or necrosis (breakdown of the skin).
• The incidence (number of cases) of ulceration or necrosis following white-tailed spider bite is not known.
• The majority of alleged cases of necrotising arachnidism in Australia are based on circumstantial evidence at best.
• There is currently no test available, clinically or experimentally, that can confirm or exclude the diagnosis of white-tailed spider bite (or any other spider bite).
• No treatment has been shown, in clinical or experimental trials, to be of particular benefit in the treatment of ulcers ascribed to white-tailed spider bites.
• Hyperbaric oxygen therapy has been used to treat ulcers of various origins, including suspected spider bite, with some success. There are case reports of its success in the healing of some ulcers thought to be due to spider bite, but no controlled trials have been conducted.