Answer:
Sciatica is usually caused by a back condition such as a slipped disk, which pinches the nerve.
A friend of mine sees a chiropractor who pops her back into place. (I wouldn't recommend trying this on your own, you will likely only worsen the problem.)
Avoiding heavy lifting is a good plan, too. Or if you must lift, know how to do it properly.
Arthritis medication can help by alleviating the pressure to the nerve. However, it is a good idea to see your doctor before treating any conditions on your own.