Why do common household items (shampoo, toothpaste, medicine, etc.) have expiration dates and what happens once the expiration date passes?

Question

Why do common household items (shampoo, toothpaste, medicine, etc.) have expiration dates and what happens once the expiration date passes?

In: Other

Answer 1

Often skincare products don’t have an expiry date but have a symbol that indicates the number of months it should be usable after opening (6, 12, 24, and 36). My understanding is that these products have potential to get contaminated as you use them – sticking your fingers into a jar of moisturizer, for example – and the month guidelines are related to how the product is used and whether it has preservatives.