Rattle snakes are the leading cause of snake bites in the USA.
Bites are usually provoked, "intoxicated (drunk) young man who sees snake and still approaches it".
Local: swelling, severe pain, tingling.
Systemic: weakness, anxiety, nausea and vomiting, bleeding, perspiration,heart failure.
No local symptoms within 1 cm of fang marks after 1 hour - ? no or minimal envenomation
No edema or erythema in the area of the bite after 6–8 hours = no envenomation
Local: splint or immobilise. DO NOT INCISE OR SUCTION BITE WOUND
Envenomation: Crotaline antivenom ("antivenin" )