"best before" for sunblock

[Gerard]

Does anybody here have any concrete knowledge of how long sunblock stays effective, past its sell-by date? I picked up a lot of it almost free recently, and only just noticed that its best-by date is November 2023.

The info I've been able to find online is all extremely cautious, perhaps litigation-sensitive. I do see some suggestions that you should throw it out if it separates or turns beige/yellow, and mine is definitely still white and smooth.

Given that almost everything else remains good for months/years past its sell-by date (as the existing MMM thread suggests), I'd like to think I can use this stuff for a while, at least.

Thoughts?

[PoutineLover]

Not an expert but I would guess that the potency might decrease. If it still looks and smells normal, I'd use it but maybe reapply slightly more frequently.

[Adventine]

Daily sunscreen user here (even through fall and winter). My thinking is that as long as the product stays sealed until you actually use it, and it hasn't been stored in a hot car or similar, it'll be good to use past its best-by date. But then, I go through the stuff so fast that my bottles never reach their best-by date.

If I was in your place, I wouldn't hesitate to use the sunscreen past Nov 2023, as long as I knew it had stayed sealed and kept in a cool dark place.

[Catbert]

For what it's worth...I have a friend who is pharmacist by education but worked 20+ years for skin care companies.  He will eat food far beyond "use by" dates, and says most otc and prescription medicine is fine long after their "discard date".  They both, however, buy new sunblock each year.  Apparently it does use potency after a year.

[GuitarStv]

I often cycle long distances in the sun, so use sunscreen regularly.  Being cheap, I've also used sunscreen a year or two past it's expiry date.  I can confirm that expired sunscreen works better than nothing, but is not as good as fresh sunscreen.  Without sunscreen I'll burn.  I get darker tans faster with the expired stuff and need to reapply it every couple hours rather than every four hours (which is still longer than you're supposed to go with the fresh stuff) or so to avoid burning. 

[Metalcat]

For what it's worth...I have a friend who is pharmacist by education but worked 20+ years for skin care companies.  He will eat food far beyond "use by" dates, and says most otc and prescription medicine is fine long after their "discard date".  They both, however, buy new sunblock each year.  Apparently it does use potency after a year.

Same here, I ignore food dates altogether, but I don't use old sunscreen, it just doesn't work as well, and shockingly quickly after it's best before date.

I'll only use it if it's all I have access to.

[YttriumNitrate]

I've got a bottle of sunblock at my cabin that's probably close to 10 years past its expiration date. It still works, but not nearly to the degree as when new. I believe the bottle says SPF50 and I treat it like it's now SPF8.

[Gerard]

Thanks for all the replies, folks... I guess I'll use it (in heavier doses until next summer and then get some new stuff.

Apparently it can still be used for a long time as moisturizer, but as I've never used moisturizer that's something I'll have to figure out!

[GuitarStv]

Thanks for all the replies, folks... I guess I'll use it (in heavier doses until next summer and then get some new stuff.

Apparently it can still be used for a long time as moisturizer, but as I've never used moisturizer that's something I'll have to figure out!

There are enough carcinogens in typical sunscreen batches that I wouldn't use it as moisturizer.  It's way better than UV skin cancer, but no use tempting fate.

[Metalcat]

Thanks for all the replies, folks... I guess I'll use it (in heavier doses until next summer and then get some new stuff.

Apparently it can still be used for a long time as moisturizer, but as I've never used moisturizer that's something I'll have to figure out!

There are enough carcinogens in typical sunscreen batches that I wouldn't use it as moisturizer.  It's way better than UV skin cancer, but no use tempting fate.

Yeah, there's no way I would use old sunscreen as moisturizer, sunscreen is disgusting. My least favourite part of summer.

[simonsez]

If you bought decent stuff, make sure you get all you can out of it!  Those cheap plastic tube squeezers work wonders, especially the ones that are windable/turnable.

https://www.amazon.com/VITKSTAR-Toothpaste-Squeezer-squeezers-Dispenser/dp/B09SF72KNC

[Case]

Does anybody here have any concrete knowledge of how long sunblock stays effective, past its sell-by date? I picked up a lot of it almost free recently, and only just noticed that its best-by date is November 2023.

The info I've been able to find online is all extremely cautious, perhaps litigation-sensitive. I do see some suggestions that you should throw it out if it separates or turns beige/yellow, and mine is definitely still white and smooth.

Given that almost everything else remains good for months/years past its sell-by date (as the existing MMM thread suggests), I'd like to think I can use this stuff for a while, at least.

Thoughts?

When it gets past a year expiration, or even earlier, you're better just tossing it. 

Eventually it does loose substantial potency.  Trying to figure out exactly how 'aged' it is will be complex, and will depend on storage temperature and maybe how much air has gotten in.  Pretty easy to accidentally get a huge UV overdose because you thought you were protected.

I actually went thru my supply and tossed expired stuff last year.

[thedigitalone]

FDA guidance, it's good for three years unless there is an expiration date on it, if there is discontinue use after that date.

Sunscreen expiration dates

FDA regulations require all sunscreens and other nonprescription drugs to have an expiration date unless stability testing conducted by the manufacturer has shown that the product will remain stable for at least three years.  That means, a sunscreen product that doesn’t have an expiration date should be considered expired three years after purchase.

To make sure that your sunscreen is providing the sun protection promised in its labeling, the FDA recommends that you do not use sunscreen products that have passed their expiration date (if there is one), or that have no expiration date and were not purchased within the last three years.  Expired sunscreens should be discarded because there is no assurance that they remain safe and fully effective.

https://www.fda.gov/drugs/understanding-over-counter-medicines/sunscreen-how-help-protect-your-skin-sun#:~:text=Sunscreen%20Absorption%20(2019)-,Sunscreen%20expiration%20dates,for%20at%20least%20three%20years.