Rhytides%20(wrinkles) Management
Prevention
Sunscreens
- Sunscreens that block UVB radiation are readily available
- Sun protection factor (SPF) corresponds to the ratio of doses of UV radiation (predominantly UVB radiation) that result in erythema (sunburn) with protection to the doses that result in erythema without protection
- Sunscreen that is broad spectrum with minimum SPF of 30 is important in any skin care regimen to prevent photoaging as well as skin cancers
- Physical/inorganic sunscreen agents physically block UV radiation skin penetration by reflecting or scattering light
- Most common agents are titanium dioxide and zinc oxide
- Blocks both ultraviolet A (UVA) and UVB radiation
- Well-tolerated on the skin with low risk of irritation
- Chemical/organic sunscreen agents absorb the harmful UV rays and transform them to longer-wave radiation that is harmless
- Adequate application of 2 mg/cm2 (approximately ½-1 tsp) of sunscreen is imperative for sunscreen to be effective
- Less than recommended application consequently results in lowered SPF
SUNSCREEN COMPONENTS1 | |
COMPONENT | REMARKS |
UVA Absorbers | |
Avobensone (Parsol 1789) ((Butylmethoxydibenzoylmethane) | Absorbs throughout UVA I spectrum Controversy regarding potential to degrade other sunscreen ingredients and photostability |
UVB Absorbers | |
Aminobenzoic acid (Para-aminobenzoic acid) (PABA) | Not frequently used because of photocontact dermatitis and staining of clothes |
Ensulizole | Stabilize photolabile agents |
Ethylhexyl-methoxycinnamate (Octyl methoxycinnamate) | Non-staining, poor water resistance |
Padimate O, Padimate A (Para-aminobenzoic acid) | Esters of PABA but less dermatitis and staining May cause stinging |
Salicylates | Non-sensitizing, stable, water insoluble Have the ability to stabilize other agents that can prevent photodegradation |
UVA and UVB Blockers | |
Octocrylene | Filters both UVB and UVA Stabilize photolabile agents |
Oxybenzone | Absorbs both UVB and UVA |
Titanium dioxide | No photoallergic or contact properties |
Titanium dioxide (micronized) | No photoallergic or contact properties |
Zinc oxide | No photoallergic or contact properties |