<s>[INST] I am a student and needing to figure out a diagnosis with very little to go on...a 72 year old witChatDoctorplaints of rash near the gluteal fold on the right side. painful vesicular rash p=onset 2 days ago, no fever but occasional burning and sensitivity at the site. has applied triple antibiotic oint without relief. Widowed for 10 years with a steady boyfriend with whom she became sexually active with recently.. any suggestions? [/INST] This sounds like it might be herpes, either genital herpes, or given her age, herpes zoster (shingles). An initial outbreak of genital herpes (herpes simplex) can be quite painful. Shingles is caused by the same virus that causes chickenpox, and most often occurs in older people and is quite painful. The rashes from both viruses can look the same. They both can be treated by the same antiviral, acyclovir and other variants of it. Hope this helps. </s>