Could you tell me if drug screens at a pain management clinic test for naloxone?

Not specifically: but in my experience, larger amounts of it, like in people on Suboxone 8/2 who are taking 3-4 tablets a day can come up positive for opiates, and when tested for each specific opiate (morphine, codeine, oxycodone, oxymorphone, hydromorphone, hydrocodone) they all test negative. So, I think that Naloxone in high doses can come up positive for opiates. There are specific tests for buprenorphine.

Naloxone: The only reason to check for naloxone is if the patient is suspected of using Suboxone however the confirmation of a drug screen may include Naloxone