Are we talking about utilitarian arguments regarding the addicts themselves, or the effect on the wider community? Addicts don't die without effecting their friends, family and communities negatively.
Short answer, though, assuming we're talking developed Western nation, and considering a full Naloxone kit costs ~$40, I really don't think "greatest good for greatest number" triage is an appropriate paradigm. If we're talking about something with expensive, limited supply, like donor organs, that would be very different.