If you do not have a bottle brush, take some uncooked rice or beans and pour about 1 tbls into your sippy cup. Add in 1 tsp of dish soap along with 1 tbls water. Screw the lid on tight, and shake shake shake! The rice or beans will act as an agitator to help remove larger pieces of accumulated gunk.

Should I sterilize sippy cups?

How Often Should I Clean and Sanitize My Child's Sippy Cups? Sippy cups should be checked, washed, and sanitized on a daily basis. Because sippy cups have small crevices in the mouthpiece portion of the cup, this makes them an easy place to develop mold growth.

How often should you wash sippy cups?

Wash Them by Hand

“Every so often, depending on the frequency of use, sanitize the tops in boiling water for two minutes.” But if you're using the dishwasher, Lemond suggests using the sanitize cycle and heat drying option, which will help eliminate lurking bacteria from all plastic and glass containers.