Antivenin can apparently only be given at a hospital due to rare cases of extreme allergic reactions. It's best to inform the closest hospital asap if possible so the proper antivenin can be acquired by the time you're there(it may have to be flown in from somewhere). I can't locate the source for it but I think keeping the bite lower than the heart is the idea, gravity working to keep the venom in the extremity(if it's in an extremity). Someone may know better. Apparently, fatalities in the states are extremely rare.
I am an Emergency Room Charge Nurse, and treat dozens of snake bites a year. Here in Virginia, the Copperhead is the most common, but we do have Rattlers in the Blue Ridge Mountains, and Coral Snakes on the coast. With the exception of the Coral Snake, all venemous snakes in the US are in the family Crotalidae, and the antivenin I use to treat Copperhead and Rattlesnake bites is CroFab.
Crofab is a dehydrated spun down sheep serum that is a mixture of serum from sheep that have been envenomated with 4 different species of Crotalidae, and then are combined into one product. The vials of antivenin contain a flacky white cake of dehydrated serum which resembles Splenda that has clumped together, and when reconstituted with sterile water, takes roughly 30 minutes of slow swirling of the vial to properly mix. The first treatment dose is 4 to 6 vials diluted into a 250ml bag of normal saline, and is infused over an hour, with the patient monitored for vital signs and the bite site monitored for progression vs arrest of pain & swelling. These patients are admitted to the hospital, and may require additional 2-vial doses every 6 hours, for up to 18 hours (or 3 doses). Allergic reactions to Crofab are very rare, compared to the old equine based antivenins.
The old equine based Polyvalent Antivenin, which was prepared from the serum of horses that had been hyper-immunised with snake venoms, is not really used much anymore due to the high instances of allergic reactions in patients. We used to pre-medicate patients with Solu-Medrol, Benadryl, and Pepcid prior to giving small sub-Q test injections of polyvalent in order to guage the level of reaction they may have had. I believe that Interkom may have even stopped producing Polyvalent.
At any rate, none of this treatment is possible in the field.
Additionally, FYI the cost of the antivenin is several thousand dollars PER VIAL, so a single hospital stay for snakebite can easily cost 20,000-45,000 in medications alone. All this to say, please avoid the snakes and be careful :coffeedrink: