I am having the EXACT SAME problem. I recently started using Selsun Blue and Head and Shoulders shampoo. That is the ONLY thing different that I have been using, and now can't because of a horrible sulfer odor. My husband said he has to try really hard to smell it and that it's only faint to him. I just know I smell like a lit match and how can I be the only one who smells it?? It happens if I start sweating after using any sulfate based shampoo product. She is NOT a hypochondriac ( not with this anyway).