Just want to clarify- you do NOT want plain peroxide (the wound-care stuff in the brown bottle). Benzoyl peroxide is a totally different thing- it’s an OTC medication that’s really common in acne spot treatments. As an aside, it can be really drying until you build up a tolerance, and the higher the percentage, the more drying it is. Studies have found that anything over 5% is really drying but no more effective, so look for something with 2.5-5% active ingredient.
I’m not a doctor, but just from my adventures in sensitive/acne-prone skindom, it reminds me of a couple of things. As others said above, it takes 6-8 weeks for skin to turn over, so give each fix some time before trying something new.
First thing to rule out is that the masks are just simply trapping dirt there, with maybe some extra irritation. I’d look for masks that fit snugly on the borders, but give you a little air pocket around your nose and mouth, and are made from softer fabrics. Bonus points if you can find something moisture-wicking (not cotton). I’d also take a break once or twice a day to either use a gentle face wipe or even just splash water on your face to keep the dirt down. If there’s a particular problem area, it’s ok to apply the benzoyl peroxide regularly in that spot, but I’d avoid using it all over your face. If it makes that area red or dry, use it every other day until you tolerate it better, then increase to once a day.
Second thing that I’ve gotten specifically in warm weather is dermatitis, which is just a mild bacterial irritation from sweat and close fabric contact. I usually get it when I exercise in more form-fitting tops in the summer. That goes away with a mild antibiotic cleaner for a few days as needed. Since this is usually more harsh on skin, I’d see if the above works first.
Finally, chin-area acne in adult women is often tied to hormones, and won’t really change until they do. You could talk to your doctors about different birth control options that are better for acne, or a dermatologist about others meds. The only thing finally changed mine was spironolactone, which is a blood pressure medication that can also be used with lower doses to control hormonal acne.
Also, what kind of sunscreen are you using? Make sure it says either “won’t clog pores” or “non-comedogenic” (same thing), otherwise that could be contributing to your problem. I like the Neutrogena Sport Face since it’s non-clogging, but also on the sweatproof side.
