We don't use antibiotics unless we're dealing with a very high fever or something that will not go away. The first and only time she's ever taken one (for an ear infection) she had an allergic reaction. It's what spurred my interest in home remedies. Since then we've fought off stomach bugs, allergies and ear infections from home.
When my daughter shows allergy or sinus infection symptoms we put the cool mist humidifier in her room overnight. I give her warm things to drink and any food she asks for. And she usually asks for fruit, soup and maybe potatoes or toast. (Obviously I don't pull out junk food and eat in front of her or she'd ask for that.) She's a great little judge of what her body needs. Remember dairy causes mucous to get thicker so if you can cut back on it for a few days it would be helpful.
To help our allergies we take a spoonful of local honey every other day or so. It contains local pollen and helps build up a tolerance. I also use all homemade cleaners, b/c I found the store bought ones caused an itchy throat & watery eyes.
It's rough when they haven't quite figured out how to blow their nose. Lots of handwashing & bring home any pillows/blankets from daycare & wash as often as possible. Wash her linens at home as often as possible right now, too.