Cheryl, silica gel is used to absorb moisture in many different products, and is usually packaged in plastic cylinders or paper packets. You’ve probably seen those little packets that say “DESSICANT—DO NOT EAT!” in medications, leather goods, vitamins and even some pasta products. Silica gel is also used in certain cat litters to absorb moisture.
While it is indeed true that it is not meant for consumption, silica gel usually produces only mild stomach upset, which typically resolves with minimal to no treatment. If very large quantities are eaten, however, such as with ingestions of multiple packets or mouthfuls of kitty litter, intestinal obstruction is possible—especially in very small animals.