It didn’t happen until I was off the medication for about 4 days.  Fortunately at the time I lived across the street from a hospital.  It began with my lower lip swelling and then my eyes got itchy and I basically got the hives all over my body.  Which is something I suffered from for several years many years prior to this occurrence.  Unfortunately this time I got them in my throat and I began having difficulty breathing.  The emergency room took me immediately and gave me two different shots before they even finished taking my information because I was so bad.  My allergist is convenience that it was the Bactrim but as I mentioned earlier he wasn’t sure if it was the sulfa or the other ingredient that is found in thyroid medication.  I’m not saying that she will have a reaction at all I just know many that are allergic to that medication and I just want to make you aware.  It’s a great medication if you can tolerate it.  The thing with that med is that a reaction doesn’t always happen the first time you take it or even while you are still taking it.  It needs to build up in your system to have a reaction.

Good Luck and I hope she is better soon.