Thanks for posting your query. I can understand your concern.
This is shingles, also called herpes zoster.
The treatment for it would be taking anti viral medication called valacyclovir. You will need a prescription from your doctor for it.
You will also benefit from application of an antibiotic cream like neosporin or mupirocin to the affected area.
In case of any pain you can take paracetamol tablet for it.
Please let me know if you have any queries.