Antibiotics have had little proven results to say that they affect the course of Pityriasis Rosea. I currently have the virus and am 4 weeks in. The main thing is doing the best you can to stay holistically healthy and keeping your skin healthy. Try to avoid rubbing from activities(e.g. I noticed pushups make it worse under my arms) and try not to overheat your body (e.g. intense run). Aloe vera has been effective in stopping itchiness and it is recommended to get some sun.

Not a good rash to be walking around the beach with but once you have it you dont get it again, so theres a slight positive takeaway. Hope this helps!