SUNSCREENS
©1997, Constantinos D. Verros, MD
Active
ingredients in Sunscreens
Vehicles
& Preservatives that can cause contact
dermatitis
Sunscreen
formulations in Greece (Greek
only)
References
ACTIVE INGREDIENTS IN SUNSCREENS
Commonly used SUNBLOCK agents
Zinc Oxide
Talc
Titanium dioxide
Red vetenary petrolatum
Combinations
DISADVANTAGES : Cosmetically unacceptable, they tend to be messy and can stain clothing.
PABA and PABA Esters
Their primary protective range is found in the UVB range (290-320 nm).
PABA (260-313
nm)
Padimate O (290-315)
Padimate A (290-315)
Glycerol aminobenzoate (260-315)
ADVANTAGES : Water and
perspiration resistant.
DISADVANTAGES : Contact and photocontact allergy (PABA >
Esters), PABA stains (Esters stain rarely).
BENZOPHENONES
Their primary protective range is found in the UVA range (320-400 nm).
Oxybenzone (270-350 nm)
Dioxybenzone (206-380)
Sulisobenzone (250-380)
ADVANTAGES : Less allergenic
than PABA, do not stain.
DISADVANTAGES : Less water resistant than PABA (so their bases in
the sunscreens are thicker and less cosmetically acceptable).
CINNAMATES
Derivatives of Cinnamon, their primary protective range is found in the UVB range (290-320 nm).
Octyl methoxycinnamate
(280-310 nm)
Cinnoxate (270-328)
ADVANTAGES : They do not stain,
good protectors.
DISADVANTAGES : Poor water resistance (frequent reapplications),
may cause cross reaction allergy in persons allergic to Balsam of
Peru, tolu balsam, coca leaves, cinnamic oil.
SALICYLATES
Their primary protective range is found in the UVB range (290-320 nm).
Homosalicylate (290-315
nm)
Octyl salicylate (260-310)
Triethanolamine salicylate (269-320)
DISADVANTAGES : Octyl and triethanolamine may cause photocontact dermatitis more frequently than homosalicylate, so they are used less frequently.
DIBENZOYLMETHANES
The best UVA protectors, their protective range is found in the UVA range (320-400 nm). They offer no protection from UVB.
Tert-butylmethoxydibenzoylmethane
(310-400 nm)
4-Isopropyldibenzoylmethane (310-400)
DISADVANTAGES : Although isopropyl-DBM has been used in Europe for several years, it has not been approved for use in the USA, because of the high incidence of contact dermatitis reactions.
OTHER SUNSCREEN AGENTS
Methylanthranilate
(200-380) : With low-level broad spectrum coverage, is
added to many sunscreens to augment protection.
Octocrylene (287-323)
Etocrylene (296-383)
VEHICLES &
PRESERVATIVES THAT CAN CAUSE
CONTACT or PHOTOCONTACT DERMATITIS
| Avocado oil | t-butyl alcohol | methyl-parabens | phenyldimethicone |
| solvent red 1 | solvent red 2 |
triethanolamine stearate | benzyl alcohol |
| cetylstearyl alcohol | sorbitan sesqoiolate | imidazolidinyl urea (Germall 115) | Kathon CG |
| glyceryl monostearate | 6-acetoxy-2, 4-dimethyl-m-dioxane | carbowaxes | ethyl alcohol |
| glycerol | isopropyl alcohol | isopropyl myristate | petrolatum |
stearyl alcohol |
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Sunscreen Formulations available in Greece
(coming...Στα Ελληνικά !)
1. Melvin L.
Elson, ed. Evaluation and Treatment of the Ageing Face. Springer
- Verlag, NY, 1995.
2. O' Donoghue MN. Sunscreen: one weapon against melanoma.
Dermatol Clin. 1991;9:789-793.
3. Dromgoole SH, Maibach HI. Contact sensitization and
photocontact sensitization of sunscreening agents. In: Sunscreens:
Development, Evaluation and Regulatory Aspects, NJ Lowe, NA
Shaath, eds. Marcel Derker, NY, 1991.