Help diagnose my arm pit rash!

[TheHodgeoftheHedge]

I seem to have developed a strange discolouration/rash in one of my arm pits over the last few days. It isn’t particularly red and it’s not sore or itchy, just rather unattractive. And only in one armpit.
Any thoughts?!

Shaving rash, sweat rash ...

Not sure it’s either of those as it would be redder and sorer normally... I think...

Acanthosis nigricans. Common darkening of skin pigmentation, particularly the underarm.

That’s what I came across when googling but the images don’t seem to quite match. Mine seems to be patchier than AN but what do I know!

I had an armpit rash just like that when I started using salt deodorant. The salt was killing the bacteria which then allowed a fungal infection to grow (gross!). I used some canestan and it cleared up quick. No idea yours is same thing but whenever I get a rash I always try a bit of canestan before I go to the docs :)

I he this recently and had to change from spray deodorant to sure cream roll on. Oddly it was the sure spray that caused it and nothing cleared it up other than changing deodorants. I have get so much fresher since changing I dunno why I didn't try it sooner.

I had this problem since I started shaving my armpits and I have gone through so many stuff to use and nothing works! Until I had hair removal laser and my rash hasn't came back since! I still shave my armpits due I couldn't be able to keep up with laser payments (too expensive!) and I think heat laser stopped my rash from coming back.