Xylazine-an animal tranquilizer causing severe skin lesions in humans, please help me understand!

I know this is likely not your typical post but I am a harm reduction social worker helping some of the most vulnerable people in Philadelphia. We need your help to understand what is happening here.
Philadelphia has been hit extremely hard by the opioid epidemic which is now an overall drug and overdose epidemic. I work closely with individuals who use drugs and there has been a higher concentration an animal tranquilizer called Xylazine in the drug supply. Xylazine is not approved for human use due to severe CNS compression and was first documented as being used illicitly on a wide scale in Puerto Rico in the early 2000’s. Lab testing first identified it in Philadelphia in 2008.
In concurrence with lab results showing higher rates of Xylazine, there has been a major increase in the frequency and severity of skin lesions occurring on various places on an individuals body. This is especially concerning because the lesions are not the result of injection as they are also present in individuals with other methods of use (I.e. smoking or nasal inhalation) and in places other than sites of injection such as faces.
A couple other things:
- Primary drug of choice among individuals is most commonly fentanyl but individuals also use crack cocaine and/or methamphetamines
- Wounds are circular and crater like
- In severe cases, individuals have reported bone exposure due to erosion of the skin
- The lesions seem more common on limbs but pop up pretty much everywhere including cheeks and forehead.
Additionally, I do have photographs and while I’m not comfortable sharing them with all of Reddit, I’m more than willing to share them with concerned parties.
Due to lab testing, we know that xylazine is consistently present in the drug supply. Also, due to previous research linking xylazine to skin lesions, we know there is a relationship.
My questions are: what is the method of action underlying the skin lesions (i.e. why is this happening)? And of course, how can we best treat them?
As this substance starts to show up farther West (it was recently found in Chicago and North Carolina), it will be increasingly important for us to understand what is happening and how to help.