How long does sunscreen stay effective after being applied? If applied at home in AM, does it need to be reapplied at recess and lunch?
Today I learned that sunscreen is a banned substance at my child's elementary school due to concerns the school has about other children being allergic to it. A child must bring a note from his/her doctor saying that the child has a medical necessity for it. The school has instructed parents to apply at home in the morning. If I use SPF 50, will that last until 2:40pm when school lets out? The bottle says it has to be reapplied frequently throughout the day. Is that just marketing so they'll sell more product, or is there scientific evidence that supports the need for reapplication during the day?
Sunscreen must be applied every 2-3 hours to provide full protection. In addition, children should stay in shade as much as possible, wear a hat, and get into a habit of wearing sunglasses. If you wear a water resistant sunscreen, always apply a fresh layer after swimming and heavy sweating.
To prevent allergic reaction from a sunscreen, select PABA-free sunscreens.