ABSTRACT
BACKGROUND: Aloe vera has been used for medical purposes since antiquity, so it is known as the healing plant or silent healer. It has been claimed that aloe has several important therapeutic properties, including wound healing, thermal injury healing and anti-inflammation and immunomodulation properties. Because of these effects, it has become an ingredient in a wide variety of cosmetic products, including night creams, soaps, shampoos, suntan lotions and cleansers. OBJECTIVE: In order to determine the anti-irritant effect of aloe vera, we compared the degree of stinging intensity caused by 10% lactic acid solution and a mixture of 20% lactic acid and 100% aloe vera. METHODS: We carried out sting tests on 34 volunteers who were all over 20 years of age and they had no past and present history of atopic dermatitis and other eczema. The lactic acid sting test consisted of a 10-minute exposure on the left cheek with 10% lactic acid solution using a Hilltop chamber and the subjects recorded the degree of stinging intensity by themselves every 1 minute during 10-minutes of exposure. We also carried out a sting test with a mixed solution of 20% lactic acid and 100% aloe vera, and we compared the intensity and onset time of the stinging sensation. RESULTS: Aloe vera had some effect to ameliorate the intensity of the stinging sensation and also to delay the time required for the stinging sensation caused by lactic acid. There was a significant difference between the two groups (p<0.05). CONCLUSION: We found that aloe vera has an anti-irritant effect on the stinging sensation caused by lactic acid.
Subject(s)
Aloe , Bites and Stings , Cheek , Cosmetics , Dermatitis, Atopic , Eczema , Immunomodulation , Lactic Acid , Plants, Medicinal , Sensation , Soaps , Suntan , Wound HealingABSTRACT
BACKGROUND: Aloe vera has been used for medical purposes since antiquity, so it is known as the healing plant or silent healer. It has been claimed that aloe has several important therapeutic properties, including wound healing, thermal injury healing and anti-inflammation and immunomodulation properties. Because of these effects, it has become an ingredient in a wide variety of cosmetic products, including night creams, soaps, shampoos, suntan lotions and cleansers. OBJECTIVE: In order to determine the anti-irritant effect of aloe vera, we compared the degree of stinging intensity caused by 10% lactic acid solution and a mixture of 20% lactic acid and 100% aloe vera. METHODS: We carried out sting tests on 34 volunteers who were all over 20 years of age and they had no past and present history of atopic dermatitis and other eczema. The lactic acid sting test consisted of a 10-minute exposure on the left cheek with 10% lactic acid solution using a Hilltop chamber and the subjects recorded the degree of stinging intensity by themselves every 1 minute during 10-minutes of exposure. We also carried out a sting test with a mixed solution of 20% lactic acid and 100% aloe vera, and we compared the intensity and onset time of the stinging sensation. RESULTS: Aloe vera had some effect to ameliorate the intensity of the stinging sensation and also to delay the time required for the stinging sensation caused by lactic acid. There was a significant difference between the two groups (p<0.05). CONCLUSION: We found that aloe vera has an anti-irritant effect on the stinging sensation caused by lactic acid.
Subject(s)
Aloe , Bites and Stings , Cheek , Cosmetics , Dermatitis, Atopic , Eczema , Immunomodulation , Lactic Acid , Plants, Medicinal , Sensation , Soaps , Suntan , Wound HealingABSTRACT
BACKGROUND: Patients with sensitive skin are those individuals who state that their skin is more sensitive than the average person. But there is no clear-cut dermatological definition to describe, or standard method to evaluate sensitive skin. OBJECTIVE: To elucidate the biophysical differences between sensitive and non-sensitive skins, we measured baseline transepidermal water loss (TEWL) and performed the lactic acid sting test. METHODS: A total of 503 people responded to self-assessment questionnaires, composed of questions about self-perception, related factors, and symptoms and signs of sensitive skin. In 55 of these, we measured baseline TEWL and performed a 10% lactic acid sting test on the malar eminence of the face using a Hilltop chamber. In the lactic acid sting test, the stinging sensation was rated by patients every 1 minute, on a 4-point scale, with cumulative stinging scores. RESULTS: The incidence of self-reported sensitive skin was 43.3% for women and 23.9% for men. The cumulative scores of the lactic acid sting test were not higher in the sensitive skin group (p>0.05). However, the onset time of the stinging sensation was faster in the sensitive skin group (p0.05) between the sensitive skin and non-sensitive skin groups. Furthermore there was no correlation between baseline TEWL and 10% lactic acid sting test in the sensitive skin group compared to the non-sensitive skin group (p>0.05). CONCLUSION: Our experiment showed that the 10% lactic acid sting test is still not an adequate or ideal method to assess sensitive skin, and another new reproducible and objective method is necessary to assess sensitive skin.
Subject(s)
Female , Humans , Male , Bites and Stings , Incidence , Lactic Acid , Self Concept , Self-Assessment , Sensation , SkinABSTRACT
BACKGROUND: Sensitive skin has been described as a skin type showing higher reactivity than normal skin and developing exaggerated reactions when exposed to internal stimulants and external irritants. The Lactic acid sting test is a widely accepted method for evaluating sensitive skin and is employed for the selection of subjects experiencing invisible sensory irritation. Tape stripping of skin is a useful method for removing stratum corneum which plays a most important part in the barrier function of the skin. Measurement of the transepidermal water loss (TEWL) is the standard method to determine stratum corneum barrier status. A disturbed skin barrier is characterized by high TEWL. OBJECTIVE: The author performed this study to compare lactic acid sting test between sensitive skin and nonsensitive skin after tape stripping, not on the face but on the forearm. METHODS: A total of 40 individuals (20 individuals of the sensitive skin group and 20 individuals of the nonsensitive skin group) were selected by the method of self-assessment questionnaires related to sensitive skin. The individuals were tested a total of 6times, at internals of 2weeks, on the volar aspects of both forearms with 10% lactic acid after tape stripping, with or without a Hilltop chamber. The frequency of tape stripping was divided according to the TEWL into 3 groups as follows: mild(increase of TEWL> or = 5g/m2h compared to baseline TEWL), moderate (> or = 10g/m2h), and severe (> or = 20g/m2h). RESULTS: When 10% lactic acid sting tests were performed after mild and moderate tape stripping of skin, irrespective of the Hilltop chamber, there were more positive responders in the sensitive skin group (p<0.05). Also statistically, there was a significant difference between the sensitive skin group and the nonsensitive skin group in the comparison of the mean values of lactic acid sting scores (p<0.05). However, when 10% lactic acid sting tests were conducted after severe tape stripping of skin, irrespective of the Hilltop chamber, there were no statistically significant difference between two groups when comparison of the positive rates and the mean values were made. CONCLUSION: The Lactic acid sting test with the Hilltop chamber, after mild and moderate tape stripping is a useful method to discover sensitive skin.
Subject(s)
Bites and Stings , Forearm , Irritants , Lactic Acid , Patient Selection , Self-Assessment , Skin , Surveys and QuestionnairesABSTRACT
BACKGROUND: Users of cosmetics and skin care products often report adverse reactions ranging from itching, stinging and dryness to intense inflammatory responses such as erythema, wheals and rashes. Sensitive skin has been described as a skin type showing higher reactivity than normal skin, and it develops exaggerated reactions when exposed to internal stimulants and external irritants. The alpha hydroxy acids (AHAs), naturally occurring organic acids which include lactic acid, glycolic acid, citric acid, malic acid and tartaric acid are all kinds of noncorrosive irritants. The lactic acid sting test is widely accepted as a marker of sensitive skin and is employed for the selection of subjects experiencing invisible sensory irritation. OBJECTIVE: This study was performed to compare the results of sting tests conducted on the sensitive and nonsensitive skin group which had been exposed to various kinds of AHAs. METHOD: A total of 50 individuals (25 individuals with a sensitive skin group and 25 individuals with a nonsensitive skin group) were selected by the method of self-assessment questionnaires relating to sensitive skin. The subjects were tested on the face with 2 variables of 5 AHA types ( with or without Hilltop chamber occlusion), at 2 weeks intervals, for a total of 10 times. RESULTS: The positive response rate of stinging in the sensitive skin group was higher than that in the nonsensitive skin group for all tests except the glycolic acid sting test using Hilltop chamber (p<0.05). The mean value of sting scores in the sensitive skin group was higher than that in the nonsensitive skin group for all tests (p<0.05). CONCLUSION: Sting tests using various kinds of AHAs are a useful method in determining sensitive skin.
Subject(s)
Bites and Stings , Citric Acid , Dental Calculus , Erythema , Exanthema , Hydroxy Acids , Irritants , Lactic Acid , Patient Selection , Pruritus , Self-Assessment , Skin Care , Skin , Surveys and QuestionnairesABSTRACT
BACKGROUND: There is no clear dermatologic definition to describe sensitive skin which usually includes subjective and psychological meanings. Some individuals exhibit exaggerated response, especially on the face, ranging from itching to intense adverse reaction like erythema, wheal, and eczema in comparison to normal ones when exposed to external irritants, allergens, environmental changes or internal stimulants. OBJECTIVE: To diagnose sensitive skin, lactic acid sting test is well known to represent a person who has subjective symptoms like itching, burning, prickling and stinging. We tried to compare several lactic acid sting tests to search for sensitive skin conveniently and rationally. METHODS: A total of 50 panelists (25 people of sensitive group and 25 people of control group, respectively) were selected by the method of self-assessment questionnaires related to sensitive skin. The panelists were tested on face, by conditioning 3 variances (5% or 10% Lactic acid, Hydration, Hilltop chamber), in 2 week intervals, 8 times totally. RESULTS: When lactic acid sting tests were performed using Hilltop chamber, there were more positive responders in sensitive group(p<0.05). There was statistically a significant difference between the 2 groups in the comparison of mean values of lactic acid sting scores (p<0.05). Sensitive group showed higher sting scores and exhibited much more difference with time (p<0.05). CONCLUSION: Our experiment showed that occlusive technique using Hilltop chamber was an inspiring and useful method of several lactic acid sting tests to find out sensitive skin.
Subject(s)
Humans , Allergens , Bites and Stings , Burns , Eczema , Erythema , Irritants , Lactic Acid , Pruritus , Self-Assessment , Skin , Surveys and QuestionnairesABSTRACT
BACKGROUND: Sensitive skin has been described as a skin type showing higher reactivity than normal skin and developing exaggerated reactions when exposed to internal stimulants and external irritants. The lactic acid sting test is widely accepted as a marker of skin sensitivity and employed for the selection of subjects experiencing invisible sensory irritation. OBJECTIVE: To carry out an epidemiological study to assess the prevalence and possible related factors of sensitive skin in a regional population, and to examine the relationship between sensitive skin and subjective irritation using the lactic acid sting test. METHODS: A total of 514 people responded to self-assessment questionnaires composed of questions about the self-perception, related factors, symptoms and signs of sensitive skin. We assessed subjective irritation using the lactic acid sting test in 54 volunteers. RESULTS: The results are summarized as follows: 1. The incidences of self-reported sensitive skin were 55.7% for women, 38.9% for men and 51.0% for all responders. 2. The family history and seasonal variation of sensitive skin were significantly more common in sensitive skin group. 3. The face especially the cheek area was the most sensitive portion of body, cosmetics were common irritants. 4. The lactic acid stinging scores were significantly higher in the sensitive skin group. CONCLUSION: Our survey indicated that sensitive skin is a common problem for people and a complex problem with genetic, individual, environmental implications and the lactic acid sting test is a valuable method to define skin sensitivity.
Subject(s)
Female , Humans , Male , Bites and Stings , Cheek , Epidemiologic Studies , Incidence , Irritants , Lactic Acid , Patient Selection , Prevalence , Seasons , Self Concept , Self-Assessment , Skin , Volunteers , Surveys and QuestionnairesABSTRACT
BACKGROUND: Subjective or sensory irritation is defined as the experience of various neurosensory discomforts such as stinging, burning and an itching sensation after using certain cosmetics and skin care products. It is unaccompanied by signs of inflammation, such as erythema, scales and edema. Subjective irritation was commonly seen in atopic dermatitis. But few studies pointed out this subject yet. OBJECTIVE: The purpose of this study was to evaluate the subjective irritation in atopic dermatitis. METHODS: In 40 fealty volunteers, (20 atopic dermatitis patients and 20 controls), we assessed subjective irritation using the lactic acid sting test. We divided the subjects into what we called stingers and non-stingers by the lactic acid sting test. To compare the two groups and to determine correlations with the lactic acid sting test, medical histories regarding stinging, DMSO testing and SLS irritation testing were undertaken. RESULTS: The results are summarized as follows: 1. A history of previous subjective sensation was significantly more common in stingers than in non-stingers (p<0.05). 2. The lactic acid stinging score and the history of subjective sensation were higher in the atopy group than in the control group. 3. There was no difference between the atopy group and the control group in the DMSO test results. There was no correlation between the results of the lactic acid sting test and the DMSO test. 4. Baseline TEWL was higher in the atopy group than in the control group. There was no difference in the (delta)TEWL between the two groups. 5. There was a high correlation between the lactic acid stinging score and the baseline TEWL in the control group (p<0.05). However in the atopy group, there was no such correlation. CONCLUSION: A history of previous subjective sensation and stinging were more common in the atopy group than in the control group. There was a high correlation between the lactic acid stinging score and baseline TEWL in the control group, but in the atopy group there was no such correlation. There seem to be other important factors leading to the development of subjective irritation in the atopy group, such as higher density of the cutaneous nerve fibers.