Cleaning & care: Before first use place in boiling water for 10 minutes. Always wash the nipple after use. Do not turn the nipple inside out during cleaning. Medela Quick Clean Micro-Steam bags (sold separately) eliminate 99.9% of all harmful bacteria and germs in just 3 minutes. Nipples may be cleaned in the dishwasher, Micro-Steamed, or boiled or washed by hand..