Male, 27, suffered from moderate acne on face/back for a few years. Did accutane last year and it did the trick except...
Halfway through accutane I started developing acne on my ass. 
And I've had it since, for a year now. It was better during the winter but both this and last summer it's been annoying me to no end. There seems to be a pattern that I always have a few pimples almost every evening but they are 90% gone in the morning.
I :
- have tried washing with salicylic acid
- have tried washing with benzoyl peroxide wash
- have tried washing with mild non-perfume soap
- have tried applying moisturizer to the area
- drink a lot of water every day and eat very healthy
- go to gym 3 times a week and running twice a week
- wear only 100% cotton underwear
- am not using fabric softener on my clothes
- am using mild non-perfume laundry detergent
- sit on my ass a lot (both at home and at work). I'm not sure if this could be the cause...
Anyway if anyone has any ideas I'll glady try anything. I'm going for a tca-peel on my face in a couple of weeks and I could bring this up to my derm, but I would be extremely embarrased to talk about it, so I'll try anything before that.
Pimples or Acne isn't common to show up on your butt. Although it is common for acne to be misdiagnosed for something such as Pityrosporum folliculitis or better yet known as PF.
You can read more about it Here
It may be the problem, most of the products used to treat this is over the counter, seeing as how it is on your butt, you shouldn't have any problems of breakouts in your previous areas.
ur clothes must b irritating ur ass then, esp if cloth is syntetic so try wearing wool pants or no pants at all ,let ass breath!
it needs proper blood cyrculaton!
Thank you for you recommendation. I sit a lot. I was using synthetic fiber as well. Im changing that.
I also went to the doctor and he thinks its a bacterial folliculitis. He gave me an oral Antibiotic(CIPRONOR) and some topical wash (Alibour water). He told me is very common in people who go to gyms.
I hope to get better. those pimples hurt my self value. 🙁
Hector