I started taking NAC about 2 weeks ago. For the first 5 or 6 days, I would start sweating with abdominal pain and nausea within 2 hours after ingestion. Now, I no longer sweat after NAC ingestion. However, if I drink a cup of coffee, I start sweating significantly by the time I finish half of the cup. I assume that the caffeine is causing this response but I do not understand why. Does anyone have any thoughts on why this happens?