I take probiotics regularly as I have an inflammatory bladder thing <not an infection> that can make me more likely to get a bladder infection and, since much of the health of the immune system stems from your gut, I do take the probiotics. The ones I take need to go in the frig. Probiotics should be alive and the best chance to keep them alive and more resistant to light, air and moisture <which happens every time you open the bottle>, is to keep them in the frig - unless- it says on the bottle that you -not- need to refrigerate. The ones I have also are non-dairy as I can't have diary. These: http://www.florajen.com/products-florajen.shtml is what I have.
I also don't want added sugar in my supplements and sometimes those cute, chewable-type supplements have sugar in them. For the same bladder reason I also ntake slippery elm and a cranberry alternative since I need to avoid cranberry which is very acidic, but I still want to reduce the chances of the bacteria sticking to the bladder wall.
My dogs also take probiotics though they usually have others one - strains that work well for people don't always have the same effect on dogs.
Supplements - unlike drugs - can take a while to build up in the body. Many times people are used to the fast action of a Western drug but that's because it's working on a symptom, not actually on restoring the body's natural balance and ability to heal itself. So supplements can take time to work, where you might see an effect. It might several weeks or months.
I used to take fish oil and a multi as well but I do canned sardines instead and most commercial multi's are too acidic for me at this point <some of the individual vitamins in a multivitamin capsule or pill, are very acidic - like vitamin C - ascorbic acid>