SUNSCREENS

INTRODUCTION

• Sunscreens are a constantly evolving component of the dermatologist's therapeutic armamentarium.

• Substances that alter UV-Radiation effects on skin by absorption and / or reflection

PENETRANCE

UVA / LONGWAVE (320-400 nm)

• Weak Erythrogenic Activity / Low Energy Waves

• Primary TANNING component ; Tan is injury by ROS to the Skin DNA; imperfect attempt to prevent further DNA damage.

• Penetrates deeper than UVB ; DERMIS

• Tanning, photoaging (Rhytides), PMLE, Seborrhiec Keratosis

UVB / MEDIUMWAVE (290 -320 nm)

• Erythrogenic activity is the highest; Most severe damage

• Primary BURNING component

• Sunburn, Vit D synthesis

• Responsible for inducing skin cancer

• Direct impact on cell DNA and proteins

• Actinic Keratosis / SCC / BCC

UVC / SHORTWAVE (100-290 nm)

• Absorbed near-totally by Stratospheric Ozone

• Artificial Sources - Germicidal Lamps

• ? Global Warming ? CFCs ? Supersonic Transport

• Protection depends on Latitude / Altitude / Time of Day

SOLAR RADIATION

• 94-95 % UV A• 03-05 % UV B• Insignificant UV C

• Partial and Complete Attenuation of UV B and C by Stratospheric Ozone

INDICATIONS• Sunburn / Suntan• Freckling, discoloration• Photoaging• Skin Neoplasms (Melanomas / Non-Melanomas)• Phototoxic/ photoallergic reactions• Photosensitivity diseases

– Polymorphous light eruption (290-365 nm)– Solar urticaria (290-515 nm)– Chronic actinic dermatitis (290 nm-visible)– Persistent light reaction (290-400 nm)– Lupus erythematosus (290-330 nm)– Xeroderma pigmentosum (290-340 nm)– Albinism

• Post-inflammatory hyperpigmentation (post-procedure)

CLASSIFICATION

• The last FDA sunscreen monograph was issued in 1999, with a list of 16 approved sunscreen agents.

• RE-CLASSIFY : CHEMICAL ORGANIC PHYSICAL INORGANIC

LOCAL (ORGANIC / INORGANIC)

SYSTEMIC

‘COSMETICS’ to ‘OTC’ by FDA in 1972

ORGANIC (CHEMICAL) SUNSCREENS

• Organic UV filters are active ingredients that absorb UV radiation within a particular range of wavelengths, depending on their chemical structure.

• Once the UV filter absorbs energy, it moves from a low-energy ground state to a high-energy excited state.

ORGANIC SUNSCREENS

UVB FILTERS

PABA derivatives – Padimate-O most potent UVB absorber

Cinnamates – Octinoxate (Most frequently used sunscreen ingredient) Cinoxate

Salicylates - Octisalate, Homosalate, Trolamine salicylate

Octocrylene

Ensulizole

ORGANIC SUNSCREENSUVA FILTER

Benzophenones (UVB and UVA2 absorbers)

Oxybenzone (Absorbs UVB and UVA II both)

Sulisobenzone, Dioxybenzone

Avobenzone or Parsol 1789 (UVA1 absorber)

Meradimate or Methylanthranilate (UVA2 absorber)

BROAD SPECTRUM (UVA + UVB)

Ecamsule (Mexoryl SX) patented by L’OrealSilatriazole (Mexoryl XL)Bemotrizinol (Tinosorb S)Bisoctrizole (Tinosorb M)

• Tinosorb M - Hybrid Broad-Spectrum Sunscreen(ORG + INORG / UVA + UVB)

INORGANIC (PHYSICAL) SUNSCREENSZinc oxide

Titanium dioxide

Others - iron oxide, Petrolatum, kaolin, calamine,Ichthammol (Aluminium Bituminosulfate), talc

Inorganic agents function by reflecting, scattering or UV radiation (Opaque)

Their opaque nature and "whitening effect" are an inherent disadvantage, which may be minimized by the use of micronized or ultrafine particles.

SUNSCREEN PEELS

Jessner’s Solution with resorcinol• Resorcinol 14 g• Salicylic acid 14 g• Lactic acid (85%) 14 g• Ethanol (sufficient quantity to make 100 mL)

SUNSCREEN PEELS

Modified Jessner’s Solution• 17% lactic acid• 17% salicylic acid• 8% citric acid• Ethanol (sufficient quantity to make 100 mL)

SYSTEMIC PHOTOPROTECTORS

SYSTEMIC SUNSCREENS

β-carotene / Retinol / Ascorbic acid /α-tocopherols

Selenium / PABA

Antihistamines, Aspirin, Indomethacin

Corticosteroids

ADVERSE DRUG REACTIONS

Xerosis

Contact Dermatitis (ACD / ICD)

Folliculitis

Acne

Hypersensitivity / Rash

Staining (PABA- derivatives)

SUNSCREEN INDICES

SUN-PROTECTION FACTOR (UV B)

M.E.D of photoprotected skin M.E.D of unprotected skin

L/A 2mg / cm2 of product

Low: SPF 2 - 15Medium: SPF 15 - 30High: SPF 30 - 50Highest: SPF >50

Austrian Franz Greiter (1962) …….. FDA (1978)

SIGNIFICANCE OF SPF

• SPF of 15 blocks about 93.3 % of UVB radiation, while one with an SPF of 30 blocks about 96.7 % of UVB radiation; SPF 50 98% blockage (Abs = 100- 100/SPF)

• This difference of 5% may make the difference between an aesthetically pleasing sunscreen and an undesirable one

• ‘WR’ (SPF maintained after 40-80 mins Immersion)

SPF in FITZPATRICK SCALE

Category Skin Type SPF

I Always burns, never tans 15 >

II Burns easily 15

III Burns moderately, (avg caucasian) 10-15

IV Burns minimally, tans well (olive skin”) 6-10

V Rarely burns, tans profusely (brown skin) 4-6

VI Never burns (black skin) none

PA ++

Protection against UV A (Japanese Std)

OTHER INDICES• PERSISTENT PIGMENT DARKENING (PPD) COLIPA

• IMMUNE PROTECTION FACTOR (UV A)

• BOOTS STAR RATING (01-05) <UK> MINIMAL MELANOGENIC DOSE (MMD)

APPLICATION

• All sun exposed areas (in a concentration of 2 mg/cm 2 ), and allowed to dry completely 30 -45 mins before sun exposure. It should be reapplied every 2 hours, and after swimming, vigorous activity, excessive perspiration, or towel usage

TEASPOON RULE

3 mL (slightly more than half a teaspoon)

FACE / NECK / EACH ARM

6 mL (slightly more than a teaspoon)

CHEST / BACK / EACH LEG

VEHICLES

• EMULSIONS ( O/W - W/O)• GELS / AQUAGELS• STICKS• SPRAYS• COSMETICS CONTAINING (NEUTROGENA /

VICHY / BANANA BOAT etc)

RECENT TRENDS• SUN-SPHERES

SunSpheres are Styrene/Acrylate copolymers that do not absorb UV irradiation but enhance the effectiveness of the active sunscreen ingredients.

• Scattering UVR Increased Contact with the active UV filters in the sunscreen. SunSpheres are also available in a powder form, and can boost SPF by 50 -70% making it possible to reduce the concentration of active ingredients.

MICRO-ENCAPSULATION

Active Ingredients in Silica Shell Minimal allergic or irritant reactions and incompatible sunscreen ingredients can be safely combined, without loss of efficacy.

IDEAL SUNSCREEN

INDIAN FORMULATIONS

• SPER by Wockhardt

• Zinc Oxide 2 %w/w • Oxybenzone 3 %w/w • Octocrylene 3 %w/w • Octinoxate 7.5 %w/w • Avobenzone 2 %w/w

• 100 mL Lotion @ Rs 160/-

• SPF 26

INDIAN FORMULATIONS• SUNBAN by H&H Pharma

• Octyl Methoxycinnamate 8.5% w/w• Oxybenzene 3.0% w/w• Titanium Dioxide• Micronised silica coated 6.0% w/w • Methylparaben 0.2% w/w• Propylparaben 0.02% w/w

• 60 g Cream @ Rs 385/-

• SPF 50+

INDIAN FORMULATIONS

• SHADOWZ by Dr Reddy Labs

Octinoxate, Octisalate, OxybenzoneSPF - 30Pack – 100 mlFormulation – Transparent gelColour – no colour / transparentFeel – Non greasy

75 g bottle @ Rs 290/-

INDIAN FORMULATIONS

• SUNGRACE by Glenmark• SPF 40 ; 100 mL Lotion @ Rs 325/-

INDIAN FORMULATIONS

• CETAPHIL UVA+UVB by Galderma

• SPF 50

• 400 Rs/- for100 mL Lotion

INDIAN FORMULATIONS

• SYNCOTE by Curatio

• 100 g @ Rs 249/-

INDIAN FORMULATIONS

• SUNCROS by Ranbaxy SPF 26

• Aquagel / Cream

INDIAN FORMULATIONS

• LA SHIELD by ipca

• SPF 30