Itchy red rash

My husband started taking Lovaza for a kidney disease last Saturday.  Later that day, he noticed an itchy red rash on his right arm.  We didn't pay much attention to it at first, but by Sunday it had spread to his other arm, and down his sides.  He stopped the Lovaza, and saw a doctor on Monday.  They put him on Clarinex and Methylprednisolone.  They also gave him shots of epinephrine and something else (I forget what).  By the next day the rash had spread even more to his stomach.  Tuesday he went to an allergist who told him that he basically didn't know what it was and to continue on the medications from the previous doctor.  I spoke with the allergist on Thursday and told him that the rash was still spreading.  He told me to have my husband see a dermatologist.  Friday he went to a dermatologist who gave him a spray for the itching and a second round of steroids to take by mouth.  Today the rash is even worse and spreading now down his legs.  Any suggestions?