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Local Effects

Snakebite may result in very obvious bite marks and a prominent local tissue response, but equally the bite marks may be indistinct or virtually undetectable and the local response negligible. The latter is particularly true for certain Elapid species, but a few Viperids also cause minimal local effects, similarly exerting their major clinical effects systemically.

Bite marks vary from a single fang puncture, to classic double punctures from paired fangs , through numerous punctures from both fangs and non-fang teeth , to scratches, where fangs have dragged through the skin. If two or more bites have been delivered to the same region, then an even more complex pattern may be seen. The distance between paired fang punctures may indicate the size of the snake, but is dependent on species.

The presence of associated effects may be of value in determining the most likely culprit. Thus there may be local swelling, erythema, echymosis, haemorrhage, blistering, or frank necrosis. In general it should never be assumed that the lack of a local response to a bite indicates a trivial bite, unless the snake species responsible is already known and is clearly associated with significant local effects in all medically noteworthy cases.

Pain locally is quite variable and is not always reliable as an indicator of significant envenoming.