In a word...yes.
Why...? The short answer is "to prevent infections".
You won't find any expiration dates on cosmetics, so be your own watchdog.
Recommendations are to keep your make up in a cool, dry place, away from sunlight. That covers wehre most of us make our make up, either in the bathroom - for convenience, or a dressing table near a window - to take advantage of natural light.
One solution is to get one of the cases made specificially for make up storage, such as by Caboodle.
Everyone consideres these useful for trips, but consider using it all the time. This will also control how much unnecessary stuff you keep.
So much for safe storage - how long will the cosmetics last? Keep in mind that a lot depends on the composition of the product (wet v.s. dry) and where you use it (eyes v.s. cheeks).
Mascara - when you're putting things near your eyes, take no chances - 3 months and it's time to go... Sooner if it's starting to clump or get dry. Don't try to add water or even saline - mascara's aren't water based and your brush will be covered with water and clumps.
Remember too, that aftr you touch your lashes, you're shoving that brush in the tube, so if you have an eye infection - out it goes, because the whole tube is contaminated.
Eye and Brow Pencils 2 years - (see, you don't have to replace everything 4x a year!) Sharpen before each use to avoid germs.
Eye Shadows - Liquid 12 months; Dry 2 years.
Lip Sticks - Lip Pencils 2 years. Wipe lipsticks with a tissue after each use, sharpen pencils before each use.
Blush - Powder - Cream blush 1 year; powders 2 years.
Foundations and Liquid Concealers - 1 year. Stick concealers 18 months. Liquid and stick foundations/concealers last longer if you use a sponge or brush applicator rather than putting your fingers in each time you use it.
Bear in mind that all of these rules go out the window if you develop any kind of rash or infection. Get rid of the products - they could be causing the rash or, in the case of an infection, the product may have been contaminated before you showed symptoms. Who wants to keep getting the same eye infection over and over again?
Remember that your products will last to these lengths of time if you take care of them, including keeping your brushes and other applications scrupuliously clean. A quick swish with baby shampoo til clean, squeeze to get the water out and reshape. Dry on a paper towel. If it doesn't come clean - toss and replace it.
One last item to keep in your cosmetic box: Permanent marker.
Write the date of purchase on the case, then you'll know when it's time to replace it!
For more information on cosmetic expirations, check out last years post.