sulfamethoxazole-tmp for mrsa

My daughter is 9 mo. and was diagnosed with MRSA with a abcess (abscess) on her bottom. She has been on this medicine for 5 days and now has developed a deep almost croup cough and diahria(sp). I was wondering if this could be a side effect or allergic reaction to the medicine. I have about 36 hrs til I can get into our Dr. office. I also didnt know if this MRSA could get into her lungs. I am trying to decide if I am over-reacting or if I should seek medical assitance at ER. Any prompt comments or advice would be greatly appreciated. ( Shouldnt this medicine be kicking any/all infections she may have..so why does it seem she is getting sicker?)

[Dr_Veena]

Hi,
      Thanks for writing in. MRSA infections are a difficult task for treating, as there are very less antibiotics to choose. Most commonly used drugs are vancomycin, sulfamethoxazole- trimethoprim, linezolid, mupirocin etc. As, you mentioned that your daughter has gluteal abscess, the best way to treat this condition is draining the abscess directly with concomitant use of any of the above mentioned drugs.

Coming to side effects of sulfamethoxazole-trimethoprim which should be brought to the notice of your medical practitioner are sore throat, breathing difficulty, fever, severe blistering, chest pain, diarrhea, confusion, anuria etc.
I would suggest that you discontinue the drug and visit the ER for further treatmnet.
Best.