The bright midsummer blue sky of that July afternoon was waiting just for us. Finishing our lunch of grilled cheese sandwiches and tomato soup, my 7 year-old niece Crystal and I decided to go feed the ducks. First we put our lunch dishes away, and then put on sunscreen, because blue-eyed, blonde Crystal burned easily.
The ducks were on the other side of the pond as we walked up to the landing. One duck saw us tossing pieces of our bread into the water and paddled over to one to check it out. The floating treats attracted other ducks and soon there was lively competition for each one. Laughing, we pitched our bread chunks into the quacking crowd until we ran out, and then headed for the swing sets, pumping our legs to carry us higher and higher into the cloudless sky.
Then Crystal called out, “Aunt Louise, I feel hot. ”
“Okay, head for that big tree over there; I’ll get us some water.”
Opening my pack, I grabbed a water bottle and twisted the cap off. Turning around to offer it to Crystal, I nearly dropped the bottle when I saw her. Her face had turned a bright tomato red, and her arms were only a couple of shades lighter. As we headed back home, I kept thinking, “How did she get burned so quickly?”
Helping her lie down on the sofa, I raced into the kitchen for more water and noticed Crystal’s prescription bottle sitting next to the sink. She was supposed to take one teaspoonful of the antibiotic twice a day and I’d given her the morning dose right after breakfast, leaving it out on the counter to remind me to give her the next dose at dinnertime. Could her medicine be the cause of her sunburn-like rash? Sure enough, there WAS a small yellow sticker on the side of the label warning about exposure to sunlight. Luckily, her burn faded quickly, but I’ve never forgotten how scared I was.
Exposure of unprotected skin to sunshine causes our skin to react by either “tanning” or “burning”. Sunlight contains radiation; particularly the wavelengths of ultraviolet radiation called UVA and UVB and can trigger symptoms like rash, itching and exaggerated sunburn, called photosensitivity.
Sunburn, skin cancer and accelerated skin changes such as wrinkles and spots called photo aging are caused mostly from exposure to UVB radiation. UVB rays are most intense between 10 in the morning and 4 pm, and helps our skin produce Vitamin D. UVA radiation can trigger photosensitivity reactions in people taking certain medicines. Normal sunlight has approximately 20 times as much UVA radiation as UVB, and tanning beds have even more: 96% UVA to 4% UVB wavelengths, to decrease the risk of burning.
Crystal’s antibiotic increased the sensitivity of her skin to the UVA wavelengths in the sunshine we played in that July afternoon. The sunscreen I used back then only protected her against UVB rays, not the UVA wavelengths, which trigger photosensitity or phototoxic skin reactions. Today’s sunscreen products must be formulated to protect against both UVA and UVB. The measure of how much protection a sunscreen product gives is called SPF (Sun Protection Factor). The bigger the SPF number, the better the protection. For example, if you properly apply a sunscreen with an SPF of 15, you could stay out in the sun 15 times as long without burning as you could without it.
Sunscreens come in two main types: chemical and physical. Chemical sunscreens absorb specific wavelengths of UV radiation before they penetrate your skin, while physical sunscreens reflect and scatter UVA and UVB radiation. The lighter your skin, the more quickly it can burn and the more protection you need.
If You Take a Medicine That May Cause Sun Sensitivity:
1. AVOID using tanning beds or direct sunlight if possible. If you do go outside during the day, cover up with long sleeves and a hat with a brim at least 4 inches wide, or apply sunscreen.
2. Apply sunscreen at least 15 minutes before you expect to be outside in the sun. To be most effective, sunscreens need time to bind to your skin.
3. Use enough sunscreen. The FDA estimates an adult in a swimsuit should use about 4 and 1/2 teaspoonfuls when applying sunscreen to their whole body.
4. Reapply sunscreen frequently, including after swimming or playing in the water, sweating heavily AND especially after drying yourself off with a towel.