W57Bitten or stung by nonvenomous insect and other nonvenomous arthropods

W57 is the ICD-10-CM diagnosis code for Bitten or stung by nonvenomous insect and other nonvenomous arthropods. It belongs to block W50-W64 (exposure to animate mechanical forces) and chapter 20 (external causes of morbidity). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: W57.XXXA (initial encounter), W57.XXXD (subsequent encounter) and W57.XXXS (sequela).

Don't report W57 together with the conditions in its Excludes1 note: contact with venomous insects and arthropods (T63.2-, T63.3-, T63.4-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.