I Am 67 Female 2 Weeks Ago I Got Sore

I am 67 female 2 weeks ago I got sore throat then cough congested dr said my vitals were good no fever gives me flounaise nose drops and zpack does nothing then 2 days ago < know I used coconut oil on my legs and ate lot of nuts> started am getting an itchy rash on legs and elbows I get benedryl which helps but now dr says take Claritin or allegra this itch can it be from the coconut oil and the nuts? don't have allergies I no of??? thanks how do I stop this rash thing