I AM EXPERIENCING A AN ITCHY RASH AND SWELLING IN

i AM EXPERIENCING A AN ITCHY RASH AND SWELLING IN MY FEET AND HANDS. IT STARTED SEVERAL DAYS AGO. i WOKE UP WITH MY RIGHT FOOT SWOLLEN AND A RED BLOTCHY RASH.ID APPLIED ITCH CREAM. FOOT IS STILL SWOLLEN AND RED BUT NOT NEARLY AS BAD. IT THEN SPREAD TO BOTH OF MY HANDS BUT SO FAR NO FARTHER. i HAD BACK SURGERY 2 WEEKS AGO AND AM ON OXYCODONE AND GABBAPENTON. COULD CONDITON BE RELATED TO THE MEDS OR IS THIS A TOTALLY DIFFERENT PROBLEM.