My 12 Year Old Daughter Has Been Using Triamcinolone Cream

My 12 year old daughter has been using Triamcinolone cream for psoriasis and she is suddenly getting stretch marks on her inner thighs. She hasn't grown or gained weight. I'm very upset about this, dry skin and the Dr. prescribes a permanently disfiguring cream. The cure wasn't worth the side effect which was never mentioned. We've discontinued use, when will the stretch marks stop? Or will her thighs end up looking horrible?