<human>: Over the last year or so Ive noticed a rash under the arms. Predominately under the left arm. It is black in color but does not itch. I am overweight, high blood pressure using 2 meds to control and have been using Triamcinolone acetonide to control it. Comes and goes monthly to two months..
<bot>: Hi, Rashes underarms are common due to blockage of sebaceous glands and could be due to an allergic reaction or side effects of certain medications. I would suggest you keep this area clean and Chat Doctor.  Apply a cream containing atelier acid. Apply warm compresses with a soaked towel. You should avoid touching or pricking rashes. If the condition doesn't get better than consult a dermatologist for proper examination and start treatment accordingly. Hope I have answered your query. Let me know if I can assist you further. 