If you have bathroom clutter, you have a lot of ineffective products that you'd be better off without. Stop wasting your money by letting products expire.

Cosmetics aren't required by law to have expiration dates, and the guidelines from experts vary. Many products do have expiration dates printed on the packaging, but if you don't store your products at optimal temperatures and properly sealed after each use, they might expire long before that.

There might also be an open-jar symbol with a number of months next to it on your containers. Once you open the product, you have that many months of full potency.

And, no, using 5-year-old lotion probably won't harm you. But if you're looking to cull a glut of products, aged bottles are the best place to start.

The following dates are loose guidelines, but note that the more a product is exposed to air and potential bacteria, the shorter its lifespan. Powders last longer than liquids, and liquids in pumps stay fresher longer than liquids in jars. Always handle the product after cleaning your hands, and anything that directly touches your skin should be cleaned or replaced regularly -- brushes, cosmetic sponges, eyeliner tips, mascara wands and lip liner.

Anti-aging and acne treatments Three months to a year. Serums with antioxidants can turn quickly; be on the lookout for any changes in color.

Bath oil One year to use up that gorgeous bottle with the lavender stems; don't delay.

Blush (powder), bronzer About 18 months after first use.

Blush (cream) One year after first use.

Body bleaches, depilatories Up to two years unopened or six months after first use.

Body lotion One year if opened and two to three years if unopened. The pump containers tend to stay fresh longest.

Deodorant Up to two years, but antiperspirants should have an expiration date.

Eye and lip pencils Three to five years. Sharpen them before each use as a way to preserve them and keep them clean, or dab them on a cotton ball soaked in rubbing alcohol.

Eye cream Unopened three years and one year after first use.

Eye shadow (cream) Six months after first use.

Facial moisturizer One year after first use.

Foundation, concealer About two years for oil-based and up to three years for water-based if unopened. Most of these products are designed to last up to a year, so if you don't use it up, chances are you didn't love it anyway. You should aim to use them up within six months after first use.

Hairstyling products Three to five years. Most are alcohol-based, which helps preserve the formula. Hair gel, spray typically last two to three years.

Lip balm Good up to five years unopened and one to three years after first use.

Lipstick, gloss Two to three years unopened or 18 months after first use.

Mascara, liquid eyeliner Three to four months once you start using it. Two years if unopened.

Mouthwash Three years from manufacture date.

Nail polish One year.

Nail-polish remover Good indefinitely.

Perfume About two years. To get more mileage, resist the temptation to display bottles on your vanity. Instead, keep in a cool, dark place. Or if you get a new scent that you can't fit into your rotation, keep it in its box and store it in your refrigerator.

Rubbing alcohol At least three years.

Shampoo, conditioner, shower gel About three years.

Shaving cream About two years.

Soap (bar) Up to three years.

SPF products (any) Should have an expiration date. All others, up to three years.

Sunscreen Check the package for an expiration date, but if you still have last year's opened bottle of sunscreen, you should abandon it. Aim to use it up within six months of first use; if you don't, you're probably not using it enough.

Teeth-whitening strips About 13 months.