taken up to 30 days. Children and infants may be unable to report being bitten, making it difficult to associate their symptoms with a spider bite. Symptoms seen in infants include inconsolable crying, refusing to feed and a general erythematous rash. Muscle aches and pains, and neck spasm are often seen in children over four years of age. Unlike those of some other spiders, redback bites do not necrose. Latrodectism has been misdiagnosed as various medical conditions including acute hepatitis, sepsis, testicular torsion or an acute abdomen. Treatment Treatment is based on the severity of the envenomation. The majority of cases do not require medical care, and patients with localised pain, swelling and redness usually require only local application of ice and simple oral analgesia such as paracetamol. Pressure immobilisation of the wound site is not recommended. Keeping the victim still and calm is beneficial. Hospital assessment is recommended if simple pain relief does not resolve local pain, or systemic symptoms occur. Opioid analgesics may be necessary to relieve pain. Antivenom has been historically given for adults suffering severe local pain or systemic symptoms consistent with latrodectism, which include pain and swelling spreading proximally from site, distressing local or systemic pain, chest pain, abdominal pain, or excessive sweating (diaphoresis). A significant proportion of bites will not result in envenomation or any symptoms developing; around 2–20% of bite victims have been treated with antivenom. In an Australian study of 750 emergency hospital admissions for spider bites where the spider was definitively identified, 56 were from redbacks. Of these, 37 had significant pain lasting over 24 hours. Only six were treated with the antivenom. The antivenom manufacturer's product information recommends one vial, although more has been used. Past guidelines indicated two vials, with a further two vials recommended if symptoms did not resolve within two hours, however recent guidelines state "antivenom is sometimes given if there is a history, symptoms and signs consistent with systemic envenoming, and severe pain unresponsive to oral analgesics ... however recent trials show antivenom has a low response rate little better than placebo, and any effect is less than might be achieved with optimal use of standard analgesics. The antivenom can be given by injection intramuscularly (IM) or intravenously (IV). The manufacturer recommends IM use, with IV administration reserved for life-threatening cases. In January 2008 toxicologist Geoffrey Isbister suggested IM antivenom was not as effective as IV