silver bullet blotches

[sweet_n]

Hi everybody
I'm not sure I'm asking about idioms, still here is my question
I know that "silver bullet" has already been discussed here. But "silver bullet blotches" ... I don't get it
Context: "Imagine eight or ten dope fiendts all scarred up, some toothless and muscular, some with silver bullet blotches on them listening to this pink little creature saying, "Well, we have found, of course, that many of you begin taking drugs . . because you want to be 'cool,' you want to be 'hip,' you want to be 'in.' ...
thank you in advance

[Tdol]

Could they be patches to help them fight the addiction? It's not a standard phrase as far as I can tell.

[sweet_n]

thans, tdol
well, I suppose it's about bullet scar. And silver bullet is a joke, 'cause they're junkies (and somehow werewolves?)