--- title: Everything You Need to Know About Heat Rash description: Stay safe this summer canonical: https://time.com/3948566/heat-rash/ author: TIME article:opinion: false article:content_tier: free article:published_time: 2015-07-07T19:37:42.000Z article:modified_time: 2026-02-22T09:02:02.184Z article:section: Health og:title: Everything You Need to Know About Heat Rash og:description: Stay safe this summer og:url: https://time.com/3948566/heat-rash/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltcf4875da4f51f7d6/698859f22dce01e0c69e482f/sun.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: sun og:type: article twitter:card: summary_large_image twitter:title: Everything You Need to Know About Heat Rash twitter:description: Stay safe this summer twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/bltcf4875da4f51f7d6/698859f22dce01e0c69e482f/sun.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  # Everything You Need to Know About Heat Rash by [Alyssa Clough / MIMI](https://time.com/author/mimi/) ## Alyssa Clough / MIMI Jul 7, 2015 7:37 PM UTC  Roof of modern building and blue sky Roof of modern building and blue skyGetty Images by [Alyssa Clough / MIMI](https://time.com/author/mimi/) ## Alyssa Clough / MIMI Jul 7, 2015 7:37 PM UTC [_MIMI_](https://www.mimichatter.com/) _is a Time Inc. property._ When you think of summer, you probably picture relaxing with friends and family [on the beach](https://www.mimichatter.com/you-can-now-anti-age-at-the-beach-1172832613.html?xid=embed), looking like [a bronze goddess](https://www.mimichatter.com/i-swear-by-benefit-sun-beam-1180510074.html), and fruity drinks. What you try to forget are the annoying downsides, like excessive sweating, sunburns, and heat rash. We’re all familiar (too familiar, probably) with sweating and sunburns, but what is heat rash, really? I decided to find out once and for all. I enlisted the help of Rachel Nazarian, M.D. of [Schweiger Dermatology Group](http://www.schweigerderm.com/) to get to the bottom it. Classic heat rash (doctor talk: miliaria), “is a red, sometimes itchy or painful rash that can occur after skin has been exposed to a hot or humid environment.” Also included: small blisters. Yikes. In other words, heat makes you sweat. We sweat to lower our body temperature. So when the sweat can’t escape, the skin gets angry. Cue heat rash forming. Now, prepare for your mind to be blown in a semi-embarrassing way. Heat rash technically has nothing to do with UV rays from the sun. The only true cause of heat rash is, well, heat. That doesn’t mean you should skimp on [the SPF](https://www.mimichatter.com/the-best-new-sunscreens-youll-want-to-spray-this-summer-1156860659.html?xid=embed), though. Luckily, there are ways to avoid It. Obviously, spending long periods of time outside is no good, but if that is unavoidable (especially on a long holiday weekend), wear light, breathable clothing, avoid lathering up with thick creams and ointments, and try to keep skin as cool and dry as possible. If you do begin to feel a rash developing, immediately head inside. Nazarian recommends removing any restrictive clothing items, washing the skin with cold water, and applying a topical hydrocortisone lotion to decrease the inflammation if you have it on hand. _This_ [_article_](https://www.mimichatter.com/everything-you-need-to-know-about-heat-rash-1230834414.html) _originally appeared on_ [_MIMI_](http://www.mimichatter.com/)_._ _More from MIMI:_ * [This Is What Happened After I Tried an All Coffee Beauty Regime](https://www.mimichatter.com/coffee-beauty-products-beauty-regimen-review-1236567431.html) * [Meet the Cast of TLC’s New Show ‘My Giant Life’](https://www.mimichatter.com/my-giant-life-tlc-tall-women-cast-1236587400.html) * [Science Says a Vegan Diet Will Help You Lose the Most Weight](https://www.mimichatter.com/science-says-a-vegan-diet-will-help-you-lose-the-most-weight-1236166802.html) ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/3948566/heat-rash/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/3948566/heat-rash/"},"headline":"Everything You Need to Know About Heat Rash","datePublished":"2015-07-07T19:37:42.000Z","dateModified":"2026-02-22T09:02:02.184Z","description":"Stay safe this summer","url":"https://time.com/3948566/heat-rash/","keywords":["advice"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/bltcf4875da4f51f7d6/698859f22dce01e0c69e482f/sun.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Alyssa Clough / MIMI"}],"articleSection":"Health","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/bltcf4875da4f51f7d6/698859f22dce01e0c69e482f/sun.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"sun","caption":"sun","creditText":"Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/health/","name":"Health"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/advice/","name":"advice"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/3948566/heat-rash/","name":"Everything You Need to Know About Heat Rash"}}]}] ```