Minimal erythema dose

The sun protection factor (SPF) of a given sunscreen is a measure of its effectiveness in absorbing erythrogenic ultraviolet light. It is determined by measuring the minimal erythema dose with and without the sunscreen in a group of normal people. The ratio of the minimal erythema dose with sunscreen to the minimal erythema dose without sunscreen is the SPF. Fair-skinned individuals who sunburn easily are advised to use a product with an SPF of 15 or greater. 

A study on the photoprotective effect of the topical application of 2% vitamin E and 5% vitamin C in humans showed no effect with the application of each substance alone, but an enhanced photo-protective effect after applying vitamins E and C combined, which was attributed to the regeneration of vitamin E by vitamin C.20 This enhanced effect has also been shown with the topical application of a combination of 15% ascorbic acid and 1% a-tocopherol to porcine skin.21 The combined systemic supplementation of vitamins C and E was similarly able to reduce sunburn reactions22 and to increase the minimal erythema dose (MED), a measure for individual photosensitivity, more than supplementation with either vitamin E or vitamin C alone.23,24 An oral supplementation with an anti-oxidative combination of carotenoids (P-carotene and lycopene), vitamin C, vitamin E, selenium, and proanthocyanidins (Seresis , Pharmaton SA, Lugano, Switzerland) also reduced the development and grade of UVB-induced erythema 25... 

Mireles-Rocha, H. et al., UVB photoprotection with antioxidants effects of oral therapy with d-alpha-tocopherol and ascorbic acid on the minimal erythema dose, Acta Derm. Venereol., 82, 21, 2002. 

Fuchs, J. et al., HPLC analysis of vitamin E isoforms in human epidermis correlation with minimal erythema dose and free radical scavenging activity, Free Radio. Biol. Med., 34, 330, 2003. 

Burke, K.E., Bedford, R.G., Combs, G.F. Jr., French, I.W., and Skeffington, D.R. 1992a. The effect of topical L-selenomethionine on minimal erythema dose of ultraviolet irradiation in humans. Photodermatol. Photoimmunol. Photomed. 9, 52-57. 

An instrumental UVR response dose equivalent to approximately 0.5 minimal erythema dose (MED) is delivered to each rat... 

Excipients—Ingredients that are intentionally added to therapeutic products but that do not directly exert pharmacologic effects at the intended dosage Indirect Photoeffects—Effects of an agent, vehicle, or product on the optical, structural, molecular, or physiologic properties of the skin, such that the interaction of light and skin or effects of drug in skin are altered IR—Infrared radiation 0.76-1000 pm MED—Minimal erythema dose 8-MOP—8-methoxypsoralen... 

The first case of a phototoxic skin reaction in a female elderly patient after taking the recommended daily dose of Hypericum extract for 3 years has recently been described by Golsch and colleagues [215]. The patient presented itching and edematous erythemas at skin regions exposed to light. UV-B sensitivity was found to be increased (expressed as a decreased minimal erythema dose) while no allergic reaction to Hypericum could be provoked in a prick test. 

Immunologic In a study of the effects of topical calcitriol on minimal erythema dose and skin immune responses in... 

The dose of radiation used in photo-patch testing varies between 1 J/cm and 10 J/cm in most studies. Theoretically, the largest dose that does not alone induce erythema in skin would be most likely to yield production of the photoantigen and a positive test response. Since the minimal erythema dose (MED) in... 

Skin In five patients the minimal erythema dose for UVB, UVA, and solar-simulated radiation was determined before and after... 

SMn Among 48 kidney transplant patients immxmosuppressed either by AZA (n = 32) or mycopheno-late (n = 16), AZA was subsequently replaced by mycophenolate in 23 patients. Three months after replacing AZA by MMF minimal erythema dose to ultraviolet (UV) A increased from 15 to 25J/cm (p< 0.001) and DNA 6-TG content was reduced. P53 protein expression in irradiated skin indicated reduced susceptibility to UVA-induced DNA damage. 6-TG DNA in peripheral blood mononuclear cells remained measurable for over 2 years [78 ]. 

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