Clinical ultrasonography in patients who inject drugs (the CUPID protocol): an illustrated case series.

In 2017, there were ≈47,600 opioid overdose-related deaths in the United States. US emergency department (ED) visits for suspected opioid overdose increased by 30% between July 2016 and September 2017. The current US opioid epidemic makes it critical for emergency physicians to be aware of common and uncommon infectious and non-infectious complications of injection drug use.