Is Your Old Bottle of Sunscreen Still Good?

Sunscreen Expiration Dates

Sunscreen has an expiration date because the texture and odor may change, but the active ingredients usually last much longer.
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When I clean up my car, which isn't very often, I always come across sunglasses and old bottles of sunscreen that I had been unable to find. The sunscreen cooks in my car (sometimes for a couple of years) before I've used it up. Is it still good to use? It turns out the answer to that question is "yes."

If your sunscreen has an expiration date posted on the container, then throw it away when it expires. Otherwise, sunscreen is intended to maintain its original strength for three years. After this time, you might experience some loss of effectiveness or degradation of the inactive ingredients, though most sunscreens will still maintain some potency for longer periods of time.

You are supposed to apply sunscreen liberally, so in theory, you should use about a quarter of a 4-ounce bottle every time you apply the product. You're also supposed to re-apply sunscreen after a couple of hours or after swimming or perspiring. That's a little tricky because most sunscreens are intended to be applied to dry skin 30 minutes prior to exposure so that they can bond with the skin to provide maximum protection. If you follow the instructions on the label, chances are your sunscreen won't last from one season to the next. However, if you're like me and find leftover sunscreen from the past summer or two, it's still fine to use.

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