Same as everything else, cosmetics do go bad and if you keep on using expired makeups, you are risking yourself to breakouts and skin irritation.
So how to find out if your makeup has gone bad? The first obvious thing you should do is to check the expiry date on the product (duh!).
Then threw away anything if - it smells funny / change or separation in texture / change in colour / older than 3 yrs.
Follow the guideline below. Please note that this is just a generalized estimate, which means it does not necessarily apply to all products. Liquid/cream products do not last as long as powder ones because they contain more emulsions, which are less stable and break down over time.
Foundation ---> up to 2 years
Concealer ---> up to 2 years
Pressed Powder ---> 2 years
Loose Powder ---> up to 3 years
Powder Blush/Bronzer ---> 2 years
Cream Blush ---> 12 - 18 months
Mascara ---> up to 3 months
Powder eyeshadow ---> 2 years
Cream eyeshadow ---> 12 - 18 months
Pencil eyeliner ---> 2 - 3 years
Liquid/Gel eyeliner ---> 12 - 18 months
Lipstick ---> 2 years
Lipgloss ---> 12 - 18 months
Lipliner ---> 2 - 3 years
1. Always store products in a dry, cool place and away from direct sunlight.
2. Use a clean brush/sponge/fingers for application to prevent contamination.
3. Never share your makeup with other people.
4. It is preferred to choose products that comes in a tube or pump dispenser, thus reducing the product to air and the risk of contamination will be reduced.
How to Revive your Makeup
This does not mean using old products as if they are new, this is referring to makeup that have been sitting in your bottom drawe and still in usable condition.
* Pencil eyeliners & Lipliners - Best way would be to sharpen them.
* Gel eyeliners that have dried out - Scrap off the top layer or add a tiny bit of water. (Note: NEVER apply the same method to mascara!)
* Powder products - Scrape off the top layer and spray with rubbing alcohol.