Minor rash on mouth

My cat has a minor rash on the right side of her, towards the back. I brush her teeth and did notice a slight bump about two weeks ago. Again the bump was so subtle, I wasn't sure if it was an issue or just part of her mouth. Well now that there is rash, I guess she must have picked up something. There are a number of suspects; dirty toothbrush, my fingers (?), and she loves to rub up on everything with her cheeks and chin especially shoes.

Is there anything topical I can use? My doctor recommended something like Cortaid for the other cat when she was getting undiagnosed minor rashes on her ears. I asked if it was ingested and he said the active ingredient is so miniscule, swallowing it wasn't an issue. Is there something similar I can use to clean up the rash around the mouth?

Hmmm since you don't know what the rash is, it's probably better to see the vet and get them to recommend something. It would be irresponsible for any of us to recommend a rash treatment

I read a number of threads TCS and I think Dory has acne. The minor rash now has little black flecks. Her "acne" though isn't on her chin or along the jawline, but right beneath her lips. So it's very close to her mouth.

I use porcelin and glass bowls so no plastic her. Dory does love to rub cheeks everywhere, especially my shoes. She also likes to chew too (nothing destructive).

The threads on acne recommend cleaning the area with antibacterial soap, stridex or hydrogen peroxide. And if this fails, then off to the vet. With the acne so close to her mouth, would the home care recs still stand?

You are right, this does sound like feline acne but...
because this is so close to her mouth, you might want to have your vet check Dory to be sure those spots are acne.
Once you have a definitive diagnosis, a safe treatment can be implemented.
Better safe than sorry.

I, too, recommend a trio to the vet before trying any home treatments. It may very well be acne, but only your vet can say for sure.