Grade	Description
1	Asymptomatic; local pain at envenomation site; normal vital signs
2	Muscular pain in envenomated extremity; extension of muscular pain to abdomen (if bitten on lower extremity) or chest (if bitten on upper extremity); local diaphoresis of envenomation site or involved extremity; normal vital signs
3	Generalized muscular pain in back, abdomen, and chest; diaphoresis remote from envenomation site; abnormal vital signs, such as hypertension (systolic blood pressure > 140 mm Hg or diastolic blood pressure > 90 mm Hg) and tachycardia (pulse > 100 beats per minute); nausea and vomiting; headache