Sunscreen: Presentation PDF

Sunscreen Julie Wilkinson, PharmD, MS, BCPS Learning Objectives Explain the reasons to protect skin from sun exposure Recognize risk factors for sun- induced problems Identify the ingredients in sunscreen Clarify product recommendations Instruct the proper application of sunscreen...

Sunscreen Julie Wilkinson, PharmD, MS, BCPS Learning Objectives Explain the reasons to protect skin from sun exposure Recognize risk factors for sun- induced problems Identify the ingredients in sunscreen Clarify product recommendations Instruct the proper application of sunscreen Book Chapter This lecture is based on the following: Prevention of Sun-Induced Skin Disorders by Kimberly Crosby in the Handbook of Nonprescription Drugs Clinical Resource, Shedding Light on Questions About Sunscreens. Pharmacist’s Letter/Prescriber’s Letter. July 2020. Why? - Melanoma Stage Definition 5-year relative survival rate* Localized No sign of spread 99% Regional Spread to nearby structures or lymph nodes 68% Distant Lungs, liver, or other parts of skin 30% *Based on the stage when diagnosed Melanoma Identification A is for Asymmetry: One half of a mole or birthmark does not match the other. B is for Border: The edges are irregular, ragged, notched, or blurred. C is for Color: The color is not the same all over and may include different shades of brown or black, or sometimes with patches of pink, red, white, or blue. D is for Diameter: The spot is larger than 6 millimeters across (about ¼ inch – the size of a pencil eraser), although melanomas can sometimes be smaller than this. E is for Evolving: The mole is changing in size, shape, or color. https://www.cancer.org/cancer/melanoma-skin-cancer/detection-diagnosis-staging/signs-and-symptoms.html https://www.mayoclinic.org/diseases-conditions/melanoma/multimedia/melanoma/sls-20076095?s=6 Other Warning Signs A sore that doesn’t heal Spread of pigment from the border of a spot into surrounding skin Redness or a new swelling beyond the border of the mole Change in sensation, such as itchiness, tenderness, or pain Change in the surface of a mole – scaliness, oozing, bleeding, or the appearance of a lump or bump Skin Cancer Variations with Skin Color Variety of cancer types Most common malignancy in the US Basal Cell – translucent nodule, 35-45% of neoplasms in whites smooth surface, ulcerated or crusted, 4-5% in Hispanics usually on face 2-4% in Asians Squamous Cell – slow-growing 1-2% in Blacks isolated papule or plaque Epidermal melanin filters ultraviolet (UV) radiation Later presentation in people of color Different presentation and prognosis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2757062/  Skin Lesions https://pharmacist.therapeuticresearch.com/Content/Articles/PL/2023/Jun/Educate-About-Skin-Cancer-Detection-and-Protection Risk Factors for UVR-Induced Problems Fair skin that always burns and never tans A history of one or more serious or blistering sunburns Blonde or red hair Blue, green, or gray eyes A history of freckling A previous growth on the skin or lips caused by UV exposure The existence of a UV-induced disorder A family history of melanoma Current use of an immunosuppressive drug Current use of a photosensitizing drug Excessive lifetime exposure to UVR, including tanning beds and booths History of an autoimmune disease Ultraviolet Radiation (UVR) UVA Cancer Photoaging UVB (B for burning) Degree of exposure Erythema, cancer, photoaging Cloud cover, light-colored surfaces, altitude Synthesis of vitamin D3 Water only blocks 5% When deficiency occurs, foods and Dry clothes tightly woven block light supplements should be used Wet clothes block 50% Max of 5-30 minutes of mid-day sun a Windshield glass, but not side windows, block few times per week to arms and face most UVR Highest intensity between 10 AM and 4 PM UV index reflects the noontime exposure and is impacted by ozone, altitude, season, surface UVC – filtered by ozone reflectivity, latitude, land cover “Broad-spectrum” sunscreens block UVA and UVB Damage from the Sun Sunburn – Erythema, swelling, pain peaks at 6-24 hours after exposure and lasts 72 hours Immediate tanning – lasts for 3-4 days, caused by redistribution of melanocytes Delayed tanning – lasts 10-30 days, increase in number and activity of melanocytes Protects from sunburn, but not from cancer, photodermatoses, premature photoaging, or future burns Photodermatoses Photoallergy – chemical induced reactivity to UVR or visible light, antigenic inflammatory reaction, pruritis, erythematous papules, vesicles, bullae, urticaria Phototoxicity – chemical induced reactivity to UVR or visible light, not inflammatory, occurs on first exposure and is dose related, exaggerated sunburn, pruritis, urticaria Premature aging – wrinkling and yellowing of the skin, breakdown of elastic fibers (elastosis), drying, thickening, spider vessels (telangiectasia), growths (solar keratoses, subcutaneous hemorrhagic lesions (ecchymoses) Partial List of Medications Nalidixic acid and other fluoroquinolones Voriconazole and other antifungals Doxycycline and tetracycline Chlorpromazine and other antipsychotics Sulfamethoxazole Nifedipine and other calcium channel blockers and ACE inhibitors Carbamazepine Amiodarone Lamotrigine​ Amitriptyline Vemurafenib and other chemotherapy Hydrochlorothiazide and furosemide Cyproheptadine and other antihistamines Glipizide and glyburide Chloroquine and other antimalarials Naproxen and other NSAIDs Management of Photosensitivity Prevention by minimizing sun exposure and using protective clothing and broad-spectrum sunscreens Photoallergic – discontinue the medication if possible, not dose-related, develops a day or two after sun exposure, may spread beyond exposed skin Phototoxicity – if a switch is not possible, try to lower the dose Use cool compress, topical or oral corticosteroid, oral antihistamine Weeks or months may be needed for the reaction to fade Sun Protection Factor (SPF) Time to Burn (TTB) in minutes = SPF X TTB (without sunscreen) SPF number is the multiple of the time it takes to burn SPF 15 will allow 15 times longer than usual before burning “Broad-spectrum” indicates UVA and UVB protection Substantivity – Duration of effect generally not more than 2-3 hours “Water-resistant” can only claim up to 40-80 minutes Reapplication after swimming or sweating is needed with all Above 60, increments may not be accurate American Academy of Pediatrics recommends minimum SPF of 15 and babies less than 6 months kept out of the sun American Academy of Dermatology recommends minimum SPF of 30  Goals Avoid or minimize sunburn, photosensitivity reactions, and photodermatoses in the short term Avoid skin cancer and premature aging in the long term Sunscreen Chemical/organic Physical/inorganic/Mineral Absorb UVR so that it does not Reflect UVR pass into the epidermis Scatters UV and visible light at Absorbs 85% of radiation at wavelengths 290-770 nm wavelengths of 290-320 nm Microfine and nanoparticles allow for clear products AAD* Recommended Ingredients Drug name Pronunciation Category Oxybenzone aak-see-ben-zown Chemical - Benzophenone Avobenzone ay-vuh-ben-zown Chemical - Dibenzoylmethane derivative Octisalate aak-ti-sal-ate Chemical - Salicylate Homosalate hoe-moe-sal-ate Chemical - Salicylate Octocrylene aak-tuh-cry-lene Chemical - Cinnamate Octinoxate aak-ti-nuh-zayt Chemical - Cinnamate Zinc oxide zingk aak-side Mineral Titanium dioxide tai-tay-nee-uhm dai-aak-side Mineral *American Academy of Dermatology Ingredient Considerations Octocrylene – works as a photostabilizer, preventing other sunscreens from losing effectiveness when exposed to sunlight Octocrylene and Octinoxate – cinnamate, does not adhere well to the skin on its own Avobenzone – covers part of the UVA spectrum, easily degraded in sunlight, so needs to be combined with other sunscreens to last Octisalate and Homosalate – salicylate, does not adhere well to the skin on its own Oxybenzone – primarily absorbs UVB with some UVA, safety and environmental concerns Zinc oxide and Titanium dioxide – physical, broad spectrum, opaque, micro- or nano- particles for transparent products Safety Concerns Oxybenzone has an estrogenic effect when taken orally, but the topical effect is not clinically relevant Oxybenzone is photoallergic Oxybenzone is not recommended for children or pregnant mother’s due to a birth defect Agents (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate) have shown systemic absorption and ongoing safety studies are underway Mineral sunscreens use nanoparticles to make them easier to apply and clear on the skin and clothing, and to avoid clogging pores (non-comedogenic) Nanoparticles can form free radicals and become cytotoxic and carcinogenic Most are coated to reduce formation of free radicals by 99% Free radicals that are generated are thought to be inactivated by the skin’s antioxidants Environmental Concerns Oxybenzone and others have been found to bleach coral reef, but rising water temperatures also causes it and some of the worst bleaching in the Great Barrier Reef is in areas with little human presence Hawaii has banned oxybenzone and octinoxate products Oxybenzone and octinoxate are in 70% of American products Physical sunscreens – it has been suggested that corals may be able to ingest nano-sized particles Choice of Product Spray may help with wet skin, gels for hairy areas If acne-prone, choose a “non-comedogenic” product Mineral sunscreen for sensitive skin Avoid spray to the face and do not inhale it Babies Infants younger than 6 months old should stay out of the sun If sun exposure cannot be avoided, small amount of sunscreen infrequently Mineral sunscreens are considered safest Use lightweight clothing covering the limbs and brimmed hats Guidelines for Use Generally, people do not use enough Average of a full handful to cover the whole body (4.5 teaspoons, 23 mL) Apply liberally to all sun-exposed areas 15-30 minutes prior to sun exposure Reapply every 2 hours and after swimming, towel drying, or excess sweating If “water-resistant”, reapply after 40-80 minutes according to the label Allow sunscreen to dry for 30 minutes before using insect repellent Topical medications should be applied before sunscreen and allowed to dry It is generally recommended to apply moisturizer before sunscreen, if needed Product Storage Expiration is generally 3 years Avoid storing in hot cars or under high heat Discard if left in high heat for extended period or consistency is changed Sun-Induced Photokeratitis – pain and loss of vision Uveal melanoma – affects the iris and ciliary Ocular body Damage Cosmetic sunglasses block 70% of UVB and 20% of UVA – shopping and daily activities General purpose sunglasses block 95% of UVB and 60% of UVA – boating, driving, flying, hiking Special-purpose sunglasses block 99% of UVB and 60% of UVA – ski slopes and tropical beaches