My 2 year old daughter has swollen gums, fever and bad breath for the last 4 days. we are travelling and we found a pediatrician who prescribed acyclovir sandoz. should we give it?

Virus or yeast: Either she has oral thrush which is simply a yeast infection , or likely with presence of a fever it is most likely be an oral primary herpetic gingivostomatitis (oral herpes virus). This is very common. . Often it is subclinical. It should run its course in a few days. An oral thrush is treated with topical nystatin. Whereas the oral herpes can be aided by the aciclovir if is given early.

Primary herpes infec: Based on your comments it sounds like your little on has a primary herpes infection that often presents as a sore throat. The medicine is an antiviral, so the doctor must think virus. If your are concerned that she is not getting better get a second opinion right away, if it is strep bacteria she needs antibiotics to prevent complications.