I tried this serum for a few days and the first change I noticed was that my underarms had no bad odour. I didn’t even have to wear deodorant to mask any smell, and I loved this about it. However, after about a week of using it, I developed some sort of burning and itching rash on my underarms. I generally have very sensitive skin, so I thought that maybe I had rolled on too much. If anyone were to use this for longer than I did, I would suggest maybe trying to build up the amount you use. I’ve discontinued use for now to give my underarms a break.