Excellent pharmacy/skin care blog. I was looking for info about sunscreen expiration dates.
it's the only one that provided complete info about expiration dates on sunscreen and whether they remain effective -
snip
it’s important to understand that a sunscreen’s expiration date is based on tests that a sunscreen manufacturer has conducted to demonstrate how long the product retains its efficacy and safety. If a manufacturer runs a test for only 2 years, then they can only label that a sunscreen’s efficacy is for 2 years. However, this doesn’t necessarily mean that the sunscreen will automatically ‘go bad’ or lose its efficacy the day after its expiration date. It just means that this is the duration that it’s been studied to demonstrate that it is still safe and effective. The sunscreen could very well retain its efficacy for several years more, but there is no way to know that this is the case.
In general terms, if a sunscreen doesn’t smell bad (indicating that it is most likely unsafe to use) it is probably still safe and effective. However, without testing, there is no way to know for certain. Whether you decide to use expired sunscreen depends on your appetite for risk. If you asked for my advice as a pharmacist, I’d have to tell you to throw it out.
http://blog.pharmacymix.com/is-it-safe-to-use-expired-sunscreen
