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BACKGROUND: Ultraviolet radiation (UVR) generates reactive oxygen species in skin that can play a role in skin damage, but reports about the photoprotective properties of oral antioxidant supplements are conflicting. OBJECTIVE: We examined the ability of 2 lipid-soluble antioxidants, vitamin E and beta-carotene, to reduce markers of oxidative stress and erythema in human skin exposed to UVR. DESIGN: Sixteen healthy subjects took either alpha-tocopherol (n = 8; 400 IU/d) or beta-carotene (n = 8; 15 mg/d) for 8 wk. Biopsy samples before and after supplementation were taken from unexposed skin and skin 6 h after 120 mJ/cm(2) UVR. The effects of supplements on markers of oxidative stress in skin and the minimal erythema dose to UVR were assessed. RESULTS: Supplementary vitamin E was bioavailable, the plasma concentration increased from 14.0 +/- 0.66 (x +/- SEM) to 18.2 +/- 0.64 mug/mL (P < 0.01), and the skin concentration increased from 0.55 +/- 0.09 to 1.6 +/- 0.19 ng/mg protein (P < 0.01). Supplementary beta-carotene increased plasma concentrations from 1 +/- 0.3 to 2.25 +/- 0.3 mug/mL (P < 0.05), but skin concentrations were undetectable. Before vitamin E supplementation, UVR increased the skin malondialdehyde concentration from 0.42 +/- 0.07 to 1.24 +/- 0.16 nmol/mg protein (P < 0.01), whereas oxidized or total glutathione increased from 9.98 +/- 0.4% to 12.0 +/- 1.0% (P < 0.05). Vitamin E supplementation significantly decreased the skin malondialdehyde concentration, but neither vitamin E nor beta-carotene significantly influenced other measures of oxidation in basal or UVR-exposed skin. CONCLUSIONS: Vitamin E or beta-carotene supplementation had no effect on skin sensitivity to UVR. Although vitamin E supplements significantly reduced the skin malondialdehyde concentration, neither supplement affected other measures of UVR-induced oxidative stress in human skin, which suggested no photoprotection of supplementation. Copyright © 2004 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

1. We have attempted to reduce dapsone-dependent methaemoglobinaemia formation in six dermatitis herpetiformis patients stabilised on dapsone by the co-administration of cimetidine. 2. In comparison with control, i.e. dapsone alone, methaemoglobinaemia due to dapsone fell by 27.3 +/- 6.7% and 26.6 +/- 5.6% the first and second weeks after commencement of cimetidine administration. The normally cyanotic appearance of the patient on the highest dose of dapsone (350 mg day- 1), underwent marked improvement. 3. There was a significant increase in the trough plasma concentration of dapsone (2.8 +/- 0.8 x 10(-5)% dose ml-1) at day 21 in the presence of cimetidine compared with control (day 7, 1.9 +/- 0.6 x 10(-5)% dose ml-1, P less than 0.01). During the period of the study, dapsone-mediated control of the dermatitis herpetiformis in all six patients was unchanged. 4. Trough plasma concentrations of monoacetyl dapsone were significantly increased (P less than 0.05) at day 21 (1.9 +/- 1.0 x 10(-5)% dose ml- 1) compared with day 7 (1.6 +/- 0.9 x 10(-5)% dose ml-1:control). 5. Over a 12 h period, 20.6 +/- 8.9% (day 0) of a dose of dapsone was detectable in urine as dapsone hydroxylamine. Significantly less dapsone hydroxylamine was recovered from urine at day 14 (15.0 +/- 8.4) in the presence of cimetidine, compared with day 0 (control: P less than 0.05). 6. The co-administration of cimetidine may be of value in increasing patient tolerance to dapsone, a widely used, effective, but comparatively toxic drug. [ABSTRACT FROM AUTHOR]

Background: The role of housedust-mite (HDM) allergen (Der p1) in the pathogenesis of atopic dermatitis is controversial. We tested the hypothesis that atopic dermatitis improves if amounts of HDM allergen in the home are reduced.Methods: Active treatment comprised Goretex bedcovers (placebo, cotton covers), benzyltannate spray (placebo, water), and a high-filtration vacuum cleaner (placebo, a conventional domestic vacuum cleaner). Dust was sampled monthly from the mattress covers and bedroom and living-room carpets. 48 patients (24 adults [mean age 30] and 24 children [mean age 10]) completed the 6-month study. 28 were in the active treatment group and 20 in the placebo group.Findings: The weight of dust collected from Goretex-covered mattresses had fallen by 98% at 1 month (from 386 to 9 mg/m2) with no change thereafter. Placebo covers caused a smaller reduction in dust load (361 to 269 mg/m2); the difference between active and placebo covers at 6 months was highly significant (p = 0.002). Both active and placebo treatments caused significant reductions in Der p1 concentrations in bedroom and living-room carpets and the differences between the treatments were not significant. The severity of eczema decreased in both groups, but the active group showed significantly greater improvements in severity score (difference between mean final scores 4.3 units, p = 0.006) and area affected (difference between mean final areas 10%, p = 0.006) in analysis of covariance with initial mattress dust weights and bedroom carpet Der p1 load as covariates. Reported analysis with final values for the covariates showed that most of the treatment effect was due to the reduction in mattress dust and carpet Der p1.Interpretation: The activity of atopic dermatitis can be greatly reduced by effective HDM avoidance. Methods to identify individuals who will benefit most from such measures are needed. [ABSTRACT FROM AUTHOR]