{"id":12145,"date":"2026-02-25T10:41:51","date_gmt":"2026-02-25T01:41:51","guid":{"rendered":"https:\/\/miragen.clinic\/tewl-test\/"},"modified":"2026-07-10T21:28:46","modified_gmt":"2026-07-10T12:28:46","slug":"tewl-test","status":"publish","type":"page","link":"https:\/\/miragen.clinic\/en\/tewl-test\/","title":{"rendered":"TEWL Test"},"content":{"rendered":"\n<div class=\"wp-block-group has-custom-color-1-color has-text-color has-link-color wp-elements-e8f5acb48c3b9461e9624aa9f740dce8 has-global-padding is-layout-constrained wp-container-core-group-is-layout-8060a47a wp-block-group-is-layout-constrained\" style=\"margin-top:0px;padding-top:240px;padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:240px;padding-left:var(--wp--preset--spacing--superbspacing-small)\">\n<p class=\"has-custom-color-6-color has-text-color has-link-color wp-elements-9ab3840d1f02b8c6f2441cb2a465d08f wp-block-paragraph\">Tests<\/p>\n\n\n\n<h1 class=\"wp-block-heading has-text-align-left has-custom-color-1-color has-text-color has-link-color wp-elements-4fd047bd32214dc557166bef23c5f071\">TEWL Test | Quantifying the Degree of Skin Barrier Damage<\/h1>\n<\/div>\n\n<div class=\"wp-block-group has-custom-color-2-background-color has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-353751c3 wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-xlarge);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-xlarge);padding-left:var(--wp--preset--spacing--superbspacing-small)\">\n<div class=\"wp-block-rank-math-toc-block has-custom-color-5-color has-custom-color-11-background-color has-text-color has-background has-link-color wp-elements-7e410f1f6a20d47af3b1a26a49b51546\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-xsmall);padding-right:0;padding-bottom:var(--wp--preset--spacing--superbspacing-xsmall);padding-left:0\" id=\"rank-math-toc\"><h2>\ubaa9\ucc28<\/h2><nav><ul><li><a href=\"#sec-1\">1. What Is the TEWL Test?<\/a><\/li><li><a href=\"#sec-2\">2. Why Perform the TEWL Test?<\/a><\/li><li><a href=\"#sec-3\">3. Testing Process<\/a><\/li><li><a href=\"#sec-4\">4. How to Read Results<\/a><\/li><li><a href=\"#sec-5\">5. How Our Clinic Uses TEWL<\/a><\/li><li><a href=\"#\uc790\uc8fc-\ubb3b\ub294-\uc9c8\ubb38\">Frequently Asked Questions<\/a><\/li><\/ul><\/nav><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"sec-1\">1. What Is the TEWL Test?<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">The TEWL test measures the amount of water evaporating from the skin surface (TEWL, Trans-Epidermal Water Loss) to <strong>quantify the degree of skin barrier damage<\/strong>.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote has-custom-color-5-color has-custom-color-1-background-color has-text-color has-background has-link-color wp-elements-18856209f339c0df18c0fc8cb1a86eee is-layout-flow wp-block-quote-is-layout-flow\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-xsmall);padding-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\">\n<p class=\"wp-block-paragraph\">Analogy: The skin barrier is like a fence around a house. When the fence is strong, moisture inside the house (= moisture within the skin) does not leak out. However, when the fence develops cracks, moisture escapes. The TEWL test measures &#8220;how much moisture is leaking through the fence.&#8221;  <\/p>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image alignwide size-large\"><img decoding=\"async\" src=\"https:\/\/miragen.clinic\/wp-content\/uploads\/2026\/06\/skin-barrier-tewl-measurement-EN.png\" alt=\"Infographic illustrating the skin barrier function test that measures the amount of water evaporating from the skin surface (TEWL, Trans-Epidermal Water Loss) to quantify the degree of skin barrier damage\" class=\"wp-image-5289\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"sec-2\">2. Why Perform the TEWL Test?<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">Atopic dermatitis, rosacea, and seborrheic dermatitis are all closely associated with skin barrier damage.<sup><a style=\"color: inherit;\" href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/32199994\/\" target=\"_blank\" rel=\"noopener\">1<\/a><\/sup> However, <strong>the extent of skin barrier damage cannot be determined by visual inspection alone.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Through the TEWL test:<\/p>\n\n\n\n<ol class=\"wp-block-list has-custom-color-5-color has-text-color has-link-color wp-elements-d49d47da2b634d4ec3aa59f6b3995359\">\n<li>The degree of barrier damage can be objectively assessed<\/li>\n\n\n\n<li>Pre- and post-treatment comparisons can confirm whether the skin barrier is actually recovering.<sup><a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/38531691\/\" target=\"_blank\" style=\"color: inherit;\" rel=\"noopener\">2<\/a><\/sup><\/li>\n\n\n\n<li>Even when visible symptoms appear similar, treatment approaches may differ depending on barrier status<\/li>\n<\/ol>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Tip: &#8220;Cases where symptoms appear improved but the barrier remains weak&#8221; and &#8220;cases where symptoms persist but the barrier has recovered&#8221; require different treatment plans. Numerical confirmation enables more accurate clinical judgment. <\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"sec-3\">3. Testing Process<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n\n<ol class=\"wp-block-list has-custom-color-5-color has-text-color has-link-color wp-elements-0b99a75ea27101cdff727664889791bc\">\n<li>Prepare the test area: The skin at the test site (typically the face, inner arm, etc.) is gently prepared<\/li>\n\n\n\n<li>Measurement: A small measuring device is lightly placed on the skin surface, and water evaporation is measured within seconds<\/li>\n\n\n\n<li>Review results: Measurements are available immediately, and the medical staff will explain them right away<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>The test is completely non-invasive, with no pain or irritation whatsoever.<\/strong> The procedure takes approximately 1\u20132 minutes.<\/p>\n\n\n\n<figure class=\"wp-block-image alignwide size-full\"><img decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/miragen.clinic\/wp-content\/uploads\/2026\/02\/tewl-measurement-device-2.png\" alt=\"Diagnostic scene where skin barrier function is objectively measured by placing Transepidermal Water Loss (TEWL) measurement equipment on the back of a patient's hand.\" class=\"wp-image-4123\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"3-1-&#xAC80;&#xC0AC;-&#xC804;-&#xC8FC;&#xC758;&#xC0AC;&#xD56D;\">3.1 Pre-Test Precautions<\/h3>\n\n\n\n<ul class=\"wp-block-list has-custom-color-5-color has-text-color has-link-color wp-elements-99e6cd13be5ceb7dec6fcad0af27f5b0\">\n<li>Ideally, no moisturizer or cream should be applied to the test area<\/li>\n\n\n\n<li>If you have applied moisturizer before your visit, measurement after cleansing will be more accurate<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"sec-4\">4. How to Read Results<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">TEWL values are expressed in g\/m\u00b2\/h (grams of water lost per unit area per hour). <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The normal range for TEWL varies significantly depending on the measuring device, measurement site (face, arm, back of hand, etc.), indoor temperature and humidity, and individual skin characteristics.<sup><a style=\"color: inherit;\" href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/30348333\/\" target=\"_blank\" rel=\"noopener\">3<\/a><\/sup> As a result, the literature does not provide universally applicable reference values. However, based on my clinical experience, the following values correspond to each skin condition. <\/p>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-custom-color-4-color has-text-color has-link-color has-fixed-layout\"><thead><tr><th class=\"has-text-align-center\" data-align=\"center\">TEWL (g\/m\u00b2\/h)<\/th><th class=\"has-text-align-center\" data-align=\"center\">Barrier Status<\/th><th class=\"has-text-align-center\" data-align=\"center\">Classification<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-center\" data-align=\"center\">0\u20138<\/td><td class=\"has-text-align-center\" data-align=\"center\">Normal<\/td><td class=\"has-text-align-center\" data-align=\"center\">\u2014<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">9\u201315<\/td><td class=\"has-text-align-center\" data-align=\"center\">Mild damage<\/td><td class=\"has-text-align-center\" data-align=\"center\">Mild <a href=\"https:\/\/miragen.clinic\/en\/rosacea\/\">rosacea<\/a><\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">16\u201325<\/td><td class=\"has-text-align-center\" data-align=\"center\">Moderate damage<\/td><td class=\"has-text-align-center\" data-align=\"center\">Severe <a href=\"https:\/\/miragen.clinic\/en\/rosacea\/\">rosacea<\/a> \u00b7 Mild <a href=\"https:\/\/miragen.clinic\/en\/seborrheic-dermatitis\/\">seborrheic dermatitis<\/a> \/ <a href=\"https:\/\/miragen.clinic\/en\/atopic-dermatitis\/\">atopic dermatitis<\/a><\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">26 or higher<\/td><td class=\"has-text-align-center\" data-align=\"center\">Severe damage<\/td><td class=\"has-text-align-center\" data-align=\"center\">Severe <a href=\"https:\/\/miragen.clinic\/en\/seborrheic-dermatitis\/\">seborrheic dermatitis<\/a> \u00b7 Severe <a href=\"https:\/\/miragen.clinic\/en\/atopic-dermatitis\/\">atopic dermatitis<\/a><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Tip: Higher values indicate a weaker skin barrier. The same patient may have different values at different sites. <\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"sec-5\">5. How Our Clinic Uses TEWL<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">We utilize the TEWL test both at the start of treatment and for monitoring progress.<\/p>\n\n\n\n<ol class=\"wp-block-list has-custom-color-5-color has-text-color has-link-color wp-elements-2df1495cf7adc50d0ab38fa0a3580ac8\">\n<li>Initial visit: We objectively assess the degree of barrier damage and determine the treatment approach accordingly<\/li>\n\n\n\n<li>Progress monitoring: We remeasure at each visit to track the recovery trend of the barrier. <strong>If the values are decreasing, this provides objective evidence that treatment is proceeding in the right direction.<\/strong><\/li>\n\n\n\n<li>Treatment completion decision: At our clinic, when symptoms improve and TEWL values approach the normal range, we conclude treatment.<\/li>\n<\/ol>\n\n\n\n<blockquote class=\"wp-block-quote has-custom-color-5-color has-custom-color-1-background-color has-text-color has-background has-link-color wp-elements-ac9e050e2daafef4c0b17eee31b7f6ea is-layout-flow wp-block-quote-is-layout-flow\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-xsmall);padding-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\">\n<p class=\"wp-block-paragraph\">Analogy: Just as hypertensive patients regularly monitor their blood pressure, patients with skin barrier disorders regularly measure TEWL to check the &#8220;health index&#8221; of their barrier.<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity is-style-dots\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">References<\/h3>\n\n\n\n<ol class=\"wp-block-list has-custom-color-5-color has-text-color has-link-color has-superbfont-xxsmall-font-size wp-elements-c9281f19cfd581bacb44e9418714f411\">\n<li><a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/30348333\/\" target=\"_blank\" rel=\"noopener\"><em>Alexander H, Brown S, Danby S, Flohr C. Research Techniques Made Simple: Transepidermal Water Loss Measurement as a Research Tool. J Invest Dermatol. 2018;138(11):2295-2300.e1.  <\/em><\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/32199994\/\" target=\"_blank\" rel=\"noopener\"><em>Medgyesi B, Dajnoki Z, B\u00e9ke G, et al. Rosacea Is Characterized by a Profoundly Diminished Skin Barrier. J Invest Dermatol. 2020;140(10):1938-1950.e5.   <\/em><\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/38531691\/\" target=\"_blank\" rel=\"noopener\"><em>Sander N, St\u00f6lzl D, Fonfara M, et al. Blockade of interleukin-13 signalling improves skin barrier function and biology in patients with moderate-to-severe atopic dermatitis. Br J Dermatol. 2024;191(3):344-350.   <\/em><\/a><\/li>\n<\/ol>\n<\/div>\n\n<div class=\"wp-block-group has-custom-color-6-background-color has-background has-global-padding is-layout-constrained wp-container-core-group-is-layout-4c3b03bf wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-xlarge);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-xlarge);padding-left:var(--wp--preset--spacing--superbspacing-small)\">\n<h2 class=\"wp-block-heading\" id=\"&#xC790;&#xC8FC;-&#xBB3B;&#xB294;-&#xC9C8;&#xBB38;\">Frequently Asked Questions<\/h2>\n\n\n\n<hr class=\"wp-block-separator has-text-color has-custom-color-5-color has-alpha-channel-opacity has-custom-color-5-background-color has-background is-style-wide\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xsmall);margin-bottom:var(--wp--preset--spacing--superbspacing-xsmall)\"\/>\n\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list \">\n<div id=\"faq-q-a1b2c3d4\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">How much does the test cost?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>It is free of charge. At our clinic, the TEWL test is included as a standard part of the examination, so there is no separate testing fee. <\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-e5f6a7b8\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Is the test painful?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Not at all. A small device is simply placed gently on the skin surface. No needles or medications are used. The procedure is completed in 1\u20132 minutes.  <\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-c9d0e1f2\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Does a high value always mean something is wrong?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>A high value is an objective indicator that the skin barrier is weakened. However, a high value does not necessarily mean severe symptoms. TEWL reflects the &#8220;physical state&#8221; of the barrier, while symptoms result from multiple factors including immune responses.  <\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-a3b4c5d6\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">How often is the test performed?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Typically once at the initial visit, then at 2\u20134 week intervals to monitor progress. Once treatment stabilizes, the interval may be extended or measurements performed only as needed. <\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-c1d2e3f4\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Will the results differ if I apply moisturizer before coming in?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Yes, applying moisturizer can temporarily lower TEWL values. To accurately assess the true barrier status, it is best to visit without applying moisturizer to the test area. <\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Tests TEWL Test | Quantifying the Degree of Skin Barrier Damage 1. What Is the TEWL Test? The TEWL test measures the amount of water evaporating from the skin surface (TEWL, Trans-Epidermal Water Loss) to quantify the degree of skin barrier damage. Analogy: The skin barrier is like a fence around a house. When the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":12100,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-full-width","meta":{"_miragen_jsonld":"","footnotes":""},"class_list":["post-12145","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/pages\/12145","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/comments?post=12145"}],"version-history":[{"count":3,"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/pages\/12145\/revisions"}],"predecessor-version":[{"id":13034,"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/pages\/12145\/revisions\/13034"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/media\/12100"}],"wp:attachment":[{"href":"https:\/\/miragen.clinic\/en\/wp-json\/wp\/v2\/media?parent=12145"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}