My 2 Yr Old Is Recovering From RSV Still Has

My 2 yr old is recovering from RSV still has cough and runny nose and no fever though. He is having hives . What can I do to help relieve the itching? I'm using calomine lotion but was wondering if benadryl or oxyhives would be OK to give him. Anything else I could do to make him more comfortable and not itch.