Bite is initially painless
Mild reaction (most common)
Mild erythematous lesion that later becomes firm and heals without scar
Severe reaction
Begins with mild-severe pain several hours after bite accompanied by erythema and swelling
Hemorrhagic blister then forms surrounded by vasoconstriction-induced blanched skin
By day 3 or 4, hemorrhagic area may become ecchymotic
Leads to "red, white, and blue" sign (erythema, blanching, ecchymosis)
By end of first week, ecchymotic area may become necrotic with eschar formation
Systemic effects (rare)
Occur predominantly in children 24-72hr after the bite
Nausea/vomiting
Fever, arthralgia
DIC
Rhabdo
Renal failure
Mild erythematous lesion that later becomes firm and heals without scar
Begins with mild-severe pain several hours after bite accompanied by erythema and swelling
Hemorrhagic blister then forms surrounded by vasoconstriction-induced blanched skin
By day 3 or 4, hemorrhagic area may become ecchymotic
Leads to "red, white, and blue" sign (erythema, blanching, ecchymosis)
By end of first week, ecchymotic area may become necrotic with eschar formation
Leads to "red, white, and blue" sign (erythema, blanching, ecchymosis)
Occur predominantly in children 24-72hr after the bite
Nausea/vomiting
Fever, arthralgia
DIC
Rhabdo
Renal failure
Brown recluse spider bite
Hymenoptera stings 
Armed spider bite
Mammalian bites
Octopus bite
Closed fist infection 
Funnel-web spider bite
Dog bite