There should be an expiration date on the box. The ones I just got 2 weeks ago have an expiration date of 12/2009, so they stay good for a little less than 2 years, I am guessing. You just store them at room temperature...don't have to do anything fancy.
Some members here said the generic didn't work as well as the Rowasa for them, but I've only used the generic, so I don't know. It has helped me.
Sorry to hear you have a sinus infection. Those suck big time.
24 years old
Diagnosed with UC March 2007; yet to go into complete remission
Asacol 4 tablets 3x/day
Rowasa (generic) - nightly; Canasa (1,000 mg) in the morning
Nature's Way Primadophilus Reuteri 2/day; Chewable multivitamin; Metamucil; Viactiv