Does NAC only sometimes work immediately after noise induced hearing loss or tinnitus or can it be used months after? If so, what dosage per day and how long before I would "hear" results? Thanks guys for all your help.
NAC is generally taken as a preventative measure rather than something to correct what damage has already been done. In other words, let's say you have a dental appointment and you're concerned about noise exposure from the drill. You would take a double dose of NAC the day before and the day of the procedure. A lot of folks with tinnitus take NAC regularly just in case they might get exposed to loud noise. At least that's my understanding of it.
This forum has a very long thread on NAC, here. Probably every question you might have about NAC is answered on it.