My 3 month old son was prescribed Omnicef for an ear infection, o...

My 3 month old son was prescribed Omnicef for an ear infection, once a day for ten days. I was on the same drug for a sinus infection and the doctor felt that since I was breast feeding the baby and I should be on the same drug. First dose was Sunday night. On Monday my son developed red spots on his legs. On Tuesday he woke up with a rash all over his face/ears/neck basically all over his body. It progressively got worse that day with his eye lids swelling, and his hands being swollen. The Dr. took him immediately off the antibiotic and prescribed Benadryl every 6 hours. By Thursday the rash started to go away and on Friday he was rash free. The rash on his body was a mixture of a "flat" rash and a "raised" rash. No other symptoms and was a very happy child eating and sleeping normal. I was freaking out because he just looked awful, like he was sunburned all over body. Now I want to know if this will be a permanent reaction or something he will out grow? Pharm said Omnicef is a good drug and one that the newer drugs are being developed off of. J.