Thank you for your query,
The present episode of fever, runny nose and the rash is looking as a result of viral exanthematous illness.
You can continue Tylenol
in prescribed dosage for every 6 th hourly if there is fever and you can give oral antihistamine like hydroxyzine
in prescribed dosage as it works for both cold and rash.
You can apply calamine
containing lotions externally over skin twice or thrice daily for soothing effect and to decrease itching sensation.
Consult your Pediatrician
if fever lasts beyond 24 hours for the physical examination of your child and proper management.
Thank you for your query.