sharon (Missouri) on 11/24/2020

Some people are sensitive to NAC, and it will raise the blood pressure in their lungs, make them feel breathless and raise their heart rate. So if you're taking NAC and experience shortness of breath and pounding heartbeat, it's the NAC.

I am very allergic to NAC. I also started taking niacinamide (250mg) and had the same symptoms. After doing some research online, I found that niacinamide is the precursor to NAC. So I stopped taking the niacinamide.