Some sunscreen will come with an expiration date printed on the bottle, this may mean that past that point the chemicals have degraded and are not providing you with the same protection as a new bottle.
If you have a bottle that does not have a date, you can still confidently use it for up to 3 years – as the FDA requires manufacturers to make sure sunscreens remain at full potency for at least 3 years.
Let’s not forget!: Medications.
Some medications can increase your sensitivity to the sun and its effects.
Sunscreen is key if you are on one of these medications!
The most common ones are certain antibiotics, blood pressure drugs, cholesterol drugs, and NSAIDS.