Originally Posted by coupe
Suctioning IS still the recommended field treatment.
And it's unlikely that paramedics or other emergency personnel will carry antivenin, due to the cost (~$2000/vial wholesale), relatively short shelf life (24 months stored at 2-7° C/36-46° F), and the risk of severe anaphylaxis in reaction to the antivenin.
Suctioning IS NOT the recommended field treatment [unless you are more than 24-48 hours from help---even then, its affectiveness is +/-]. The reason is that the average dayhiker was butchering his own leg and coming close to dying from blood loss, starving the tissues of blood and losing the extremity, or spreading the venom even further into the surrounding tissues.
Nowadays its rest-light tourniquet-have someone go for help. Or hike out after the venom has had time to settle in the tissues[about 20-30 min.], so that the venom doesn't race directly into your bloodstream.