Are antibiotics necessary to clear up sinus and ear infections?

I'm pretty sure I have a sinus infection and am prone to ear infections (which is kind of odd for an adult) and I don't want to go to the doctor to get antibiotics. Do these things clear up on their own eventually? I've been doing a sinus rinse 2xs daily hoping this will clear it up.
Update: Christina G - thanks for the pic. I'm going to give this a go.
Update 2: M B - that's a great idea. I'm going to add this to my list of remedies.
21 answers 21