Local inactivation of funnel-web spider (Atrax robustus) venom by first-aid measures: potentially lifesaving part of treatment.

Venom of the male Sydney funnel-web spider was injected subcutaneously into the limbs of monkeys (Macaca fascicularis), and the central movement of venom was delayed by first-aid treatment. This treatment consisted of the application of firm pressure over the site of injection and immobilization of the limb. It was found that quantities of venom as high as 2 mg were inactivated when the first-aid procedures were maintained for 24 hours. Over a six-hour period, 0.5 mg of venom could be inactivated. Since the amount of venom injected by the spider into a human victim is unlikely to exceed 0.2 mg, these findings have immediate application both to the first aid and to actual medical management of human victims.