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This can also help to treat the aftermath sun spotting that may have already occurred. Sun poisoning symptoms usually go away on their own within 7-10 days, but the best method of defense is to avoid getting sun poisoning to begin with and actively protect yourself from the sun's damaging rays. UV rays are at their most intense between 10AM and 4PM, so trying to avoid the sun through these hours will be especially important. Dermatologists recommend using "broad-spectrum" sunscreens of at least SPF 30. Broad-spectrum sunscreens block out both UVA and UVB rays. Make sure you apply it at least 15-30 minutes prior to sun exposure. A sunburn can occur after spending only 15 minutes in the sun, so applying sunscreen before going outside into the sun is especially important when being proactive with your sun protection. These white spots are not completely fixable, as the pigment is gone from the skin. Your best plan of action is to prevent the light spots from spreading, which means protecting your skin before more sun exposure. This includes things like hats and sunglasses. The more skin you have covered, the less likely you are to expose yourself to the sun's harmful rays. You might not know it, but the sun can be very damaging to your eyes. Around 20% of all cases of cataracts can be directly related to UV exposure and damage. The sun can also cause macular degeneration, which is one of the foremost causes of blindness in the US. If you are taking any medications, you will want to check out the literature that came along with them from the pharmacy. Some drugs are known to cause further sensitivity to UVA/UVB rays, which could put you at more risk for sun poisoning if you don't protect your skin. Some of these medications include some types of antidepressants, some antibiotics, some acne medications, and even some diuretics. These are only a few examples, so be sure to check yours specifically. If you no longer have the literature that came along with your prescriptions and medications, ask your doctor or pharmacist.
Stay out of the sun! Wear sunscreen daily. Wear protective clothing. Check your medications.