Pitching your old skin care products is always a little painful, but scrubs, creams, and sunscreens dont last forever. In fact, over time their active ingredients will start to lose potency. This means, that the anti-aging serum youre spreading on your skin may be useless! And funny enough, some products become stronger as the base holding them degrades. That might sound great, but a super powered product can cause your skin to get red and irritated! Also, a product thats been sitting around for too long may have become home to bacteria which can cause acne and other skin infections. OK, so! How do you know when its time to toss your dusty bottles and tubes? It would be easy if manufacturers added an expiration date on their labels, but most wont. In fact, they dont even have to! The FDA has NO regulations for how long over-the-counter cosmetics can be sold, even if the product is a cosmeseutical. Thats the fancy name for anything that alters the skins appearance, like over-the-counter wrinkle creams. To help you out: As a general rule, once you open a lotion, cream, serum, or other skincare product, youll want to toss it within six months...or one year if the products in a pump container, which can protect the product from bacteria. And products that list water as one of the first ingredients have the shortest shelf life, cause H2O encourages the growth of bacteria. Similarly, natural and preservative-free formulas are likely to become bacteria-ridden quickly. Other signs its time to toss include changes in color or in scent. And if the product has become thinner, clumpy, or has separated into layers, its time to can it. Its not ALL a guessing game, though! Things are more clear cut with PRESCRIPTION anti-aging and anti-acne treatments, as well as with sunscreens and sunblocks. Because the FDA considers these products medicinal, theyre carefully regulated and have expiration dates stamped on their labels. But be careful with your SPF! Dermatologists warn that the expiration date listed is actually the time a store can leave it on the shelf. Once sunscreen is OPEN, it really shouldnt stick around for more than six months. And if youre using sunscreen as you should--which is daily--youll never have a bottle that lasts that long anyway! If youre unsure about whether to dump that product or not, the golden rule applies: When in doubt, toss it out!