It's my understanding that some of the bacteria that is naturally on your skin can infect the pimples, causing swelling and redness. If that's true, then it seems to me that CDS could help by killing the bacteria which would reduce the swelling and redness, and with regular use, could minimize new infections.
If it was me, I'd put full strength CDS (3000 ppm) on the affected skin. It does have a strong chlorine odor, but if someone tried some on their forhead, for example, the smell might not be as bad. When they see a positive change, they could choose to use it elsewhere and put up with the smell for a minute or so to get the results they want.
I wish that I had CDS available to me when I went through my years of acne.