Using XP and Firefox.

I have been using Firefox for several years and am very satisfied. However, a medical service program I want to use only works on Internet Explorer. I spoke with tech support from the medical service and they confirm that their software only works with IE.

Can I start using IE only for this medical service, without causing problems for my system? My default browser will continue to be Firefox, but whenever I need to access the medical service, I will do so using IE.

Do you anticipate problems?