Can you use triamcinolone on your private part for an hair bump?

Won't help: Folliculitis ("hair bump") is a localized infection. Steroids like triamcinolone don't help and often make things worse, by preventing the immune system from fighting the infection. Just keep the area clean and dry; or if you have lots of them, see a doctor to confirm the diagnosis and perhaps prescribe an antibiotic. But don't use the triamcinolone.

See a provider: I encourage to see a provider to diagnosis of this bump, as it is unlikely to be the kind of rash that responds to triamcinolone.

Steroids short term!: Corticosteroids (like triamcinalone, mid potency steroid) are amazing drugs and can reduce inflammation very quickly almost miraculously. They are however meant for short term use particularly when they are in areas where skin touches skin (groin or armpits) If overused you can cause skin thinning and folliculitis, almost worsening what you are trying to treat. Use for a few days only.