Recommendations
A wilderness medicine text recommends admitting all symptomatic children, pregnant women, and patients with hypertension to the hospital after a black widow spider bite.2 The authors commented that severe pain and muscle spasm usually respond to IV narcotics or benzodiazepines.
They noted that Latrodectus antivenin may prevent systemic sequelae and should be used in pregnant women and patients with respiratory arrest, seizures, or uncontrolled hypertension. For patients with less severe symptoms, the authors recommend weighing the value of antivenin against the risks of acute hypersensitivity and delayed serum sickness. They reported that redback antivenin is effective in 94% of patients in Australia and that Australian data show anaphylaxis rates of 0.5% to 1%.