Redback Spider Bite Treatment

The Redback spider (Latrodectus mactans hasselti) is found in Australia, often in urban or disturbed environments. It is generally about 2 to 3 centimeters long with a distinctive red abdominal stripe, similar to the North American black widow spider. Only the female bite is dangerous; the spiders are not aggressive and rarely leave their webs.

Redback Spider Bites

• Redback spider bites are common, especially in summer months, numbering more than 250 cases per year in Australia. However, these spiders rarely leave their webs, therefore bites are unlikely to occur unless a hand or foot makes direct contact with the spider web. The venom contains neurotoxins, but it is a very slow-moving venom, most likely to simply cause pain.

Symptoms

• Symptoms of the Redback spider bite include pain at the site, sometimes progressing to the entire limb, local swelling, sweating, nausea, vomiting or abdominal pain and, in severe cases, paralysis. Since the introduction of the anti-venom, there have been no recorded fatalities from a Redback spider bite.

Treatment

• Some common anti-venom treatments--such as pressure immobilization--are not recommended for Redback spider bites because the venom moves slowly and is not generally life-threatening; therefore, containing the venom at the site may only result in increasing the pain. Apply an ice pack to the bite to relieve pain, and seek medical attention. Anti-venom can be given intravenously, and if the patient shows signs of improvement after one hour, they can be released.

  If the spider can be found, it should generally be brought with the patient for positive identification.