Is Benzonatate considered a barbiturate or Benzodiazepine?

OTC sleep aids with diphenhydramine will throw a false positive for benzos on an EMIT machine if you take a lot of them. There are a couple of things that will do it, but when you show a false positive it'll be on a dip stick test or an EMIT machine--a GC/MS can tell between benzos and non-benzos.