I tried Jarrow's NAC Sustain last week. 30 minutes before drinking, i took 2 pills. Then i started to drink a bottle of wine. During drinking i took 2 pills and after floored the bottle i took further 2 pills. This drinking experiment lasts 2 hours. Unfortunately NAC seems not to work. Again, i was confrontated with flushing.
As a chemistry student, i can tell u, that NAC has hardly no effect on acetaldehyde-breakdown. Cause NAC is not en enzyme, we need the same amount of NAC as acetaldehyde, respectively ethanol. Assuming that the ingested NAC-sustain is completly absorbed and not metabolized, 10 pills of NAC-sustain (10x600mg) can just neutralize 40 ml beer!
(for the interested guys: M(NAC)=163,2 g/mol; m(NAC)=6g; n(NAC)=m(NAC)/M(NAC)=36,76 mmol; so we able to neutralize 36,76 mmol acetaldehyde. As 1 mol acetaldehyde results from 1 mol ethanol, we calculate: m(ethanol)=36,76mmol x M(ethanol)= 36,76mmol x 46,07g/mol=1,694 g, V(ethanol)=m(ethanol)/d(ethanol)=1,694g/0,79g/ml=2,14ml; V(beer;5%)=2,14ml/0,05=42,8ml)