Makeup products often have a shelf life that indicates how long they are safe to use. After the expiration date, the ingredients can degrade, potentially losing their efficacy and safety. Products may develop bacteria, mold, or irritants that can cause skin reactions. For example, expired mascara can lead to eye infections, while expired foundation can cause breakouts.

It's essential to check for any changes in texture, smell, or color in expired makeup. If any of these changes are present, it's best to dispose of the product. If you choose to use expired makeup, do so cautiously, and be aware of the potential risks to your skin health.