Can sunscreen cause a prickly heat rash? (& how to avoid it forever)

Many years ago while on vacation in the Caribbean, I began experiencing a prickly heat rash from the sunscreen I was using. The incessant itching and “pins & needles” sensation were almost unbearable. I wanted to get rid of it as soon as humanly possible so I began researching how to get rid of heat rash. That’s when I learned that the sunscreen I was using was the primary cause.

Can sunscreen cause heat rash? Yes, sunscreen can cause heat rash. Some sunscreens contain ingredients that clog pores and blog your sweat glands. This can cause your body to overheat, especially when also in a warm climate, resulting in an itchy heat rash.

Prickly heat rash, or miliaria, is a skin condition where your skin’s sweat glands are blocked and you become overheated but the sweat you produce is unable to make its way to the skin’s surface to evaporate so you experience extreme irritation, itching, and a rash of small blisters.

We can’t avoid sunscreen, especially when vacationing in the Caribbean, but you can avoid the pore-clogging ones.

Sunscreen can be a leading factor causing your heat rash

Using non-comedogenic (non-pore blocking) sunscreen is absolutely essential for avoiding heat rash. Since the products on store shelves contain ingredients that are acceptable and safe, some contain ingredients the FDA has deemed “not safe” and some are determined to need more information in order to decide whether it’s safe or not.

All natural sunscreen that will NOT cause heat rash.

Products that contain fragrances, additives, and preservatives are the key culprits causing heat rash. Since these ingredients are not essential for the product to block the sun’s rays it makes sense to look for products with natural sun-blocking ingredients such as titanium dioxide and iron oxide.

Check out the table below to understand which sunscreen ingredients the FDA has deemed acceptable, safe, not safe, or in need of more information and compare against the sunscreen in your beach bag. Toss the offenders!

When I first experienced heat rash I searched high and low to find a product that was natural and effective and protected my skin from the sun. I found Natural one Organic Skincare sunscreen (Amazon affiliate link) and never looked back. Each year I purchase a fresh supply for my Caribbean vacation and summer at home.

FDA Sunscreen Active Ingredients Determinations

Active IngredientsAcceptableSafeNot SafeMore Safety Information Needed
zinc oxideXX
titanium dioxideXX
aminobenzoic acid (PABA) XX
trolamine salicylateXX
padimate OX

How to avoid getting prickly heat rash in the future

We already discussed using quality non-comedogenic sunscreen to avoid future heat rash outbreaks. Let’s explore other ways to beat the rash.

Be Smart When In Warm, Humid Climates

Avoiding warm and humid climates may sound like an obvious solution. But what if you’re from Wisconsin (hands up) and simply refuse to stop taking Caribbean vacations? Avoiding warm climates is not an option for me.

In fact, when I first got heat rash I was so bummed. I mean, really bummed because I thought it meant my trips to the beach were over. Getting away to the Caribbean is a huge part of me. I couldn’t imagine life without it.

If you’re like me and avoiding warm & humid climates is just not an option, there are other things we can do to avoid overheating.

  • As mentioned earlier, use non-pore blocking sunscreen and lotions
  • Drink lots of water
  • Don’t spend excessive time in the sun
  • Spend a lot of time in cool, shady and/or air-conditioned areas

Wearing Loose, Breathable Clothing

Choose clothing that is loose and free-flowing. Also, clothing made from fabric made of natural fibers such as hemp, cotton, and linen, will breathe and release heat that would otherwise get trapped under the clothing.

Ladies, avoid bras if you can. If not, avoid underwires that cause the bra to adhere tightly to your skin.

Opt for free-flowing palazzo pants, sundresses, loose cotton tops, and skirts. There are so many cute styles out there why wouldn’t you?

Don’t stay in your swimsuit all day. The typical swimsuit is tight-fitting and made of lycra, a fabric that does not breathe.


Options here include avoiding exercise altogether or doing it in a cool environment. If on vacation, most resorts provide a room for exercise that is indeed air-conditioned.

If you opt to exercise outdoors, be sure to wear breathable, loose, or moisture-wicking fabrics.

Exercise in the morning before the sun reaches its peak temperature may also be helpful.

Dead skin cells from a natural build-up

As a natural result of being a living human, skin cells will die and sit on our skin until removed.

For some people, dead skin cells easily wisk away from their skin on their own.

For others, they need to be coaxed by exfoliating with a loofah sponge, washcloth, or exfoliating cream.

Experts recommend washing with an antiseptic soap that not only removes the dead skin cells but removes bacteria that gather on the surface and dries the skin completely.

Folds of skin such as in babies or overweight people

Folds of the skin can cause sweat glands to clog as well as your body to overheat. Maintain an ideal weight to avoid overheating due to excess skin folds.

This is not an article on diet or exercise so I’m not gonna say much more on this topic. Besides, it’s unlikely my skin folds are going anywhere any time soon.

Let’s talk babies

Babies have underdeveloped sweat glands which prevent them from easily releasing sweat in the first place.

Add to that their adorable array of skin folds and you have a recipe for total discomfort.

Consider leaving junior at home (with a responsible adult) or wait to vacation until they’re older.

Unfortunately, I’ve been on too many Caribbean beaches listening to babies cry and whimper in their little netted area beside a sunbathing parent. My heart breaks for their discomfort. Babies can’t talk but they do communicate (hint hint). Please, keep junior out of the heat.

What does prickly rash look like?

Prickly heat rash is characterized by little bumps or pimples called “papules” and feelings of extreme irritation and itchiness. Some cases of the rash include just one or two of the characteristics, many all of them.

Here’s an example of a prickly heat rash with the papules.

Example of prickly heat rash.

When to seek help for heat rash

In the majority of cases, prickly heat rash will go away on its own without treatment. As mentioned earlier, this can take a few days. If your condition lasts longer you should consult your doctor.

To avoid making the condition worse, avoid picking at the rash or postures as it can cause a bacterial infection resulting in inflamed pustules requiring professional intervention. Means, your doctor will need to drain the postures in a sterile environment to avoid spreading and worsening the condition.

If you experience fever or chills with increased pain, swelling, redness, or warmth around the affected area you should also consult your doctor.

Your doctor may prescribe an antibiotic, in the event of a bacterial infection or to prevent one from occurring, or your doctor may prescribe an injectable steroid similar to those used for rheumatoid arthritis patients.

Related Questions

Help, I have a heat rash NOW! What can I do to get rid of it?

Heat rash typically lasts 1-3 days. During my research, I didn’t come across any known method or cure to get rid of it immediately. It just needs time. However, there are things you can do to speed up the process:

  • If you’re wearing a swimsuit or other tight clothing that doesn’t breathe, get out of it and into clothing that is made of light, breathable fabric.
  • If you’re in a hot, humid environment, get out of it and into a fan-cooled or air-conditioned environment.
  • If you’re engaging in an activity that causes sweating, stop.
  • If you applied a cream, lotion, or ointment that clogs the pores, take a shower and wash off any remaining residue of the substance.
  • Apply calamine lotion or a menthol/camphor-based product to alleviate the itching
  • Apply a topical steroid cream like Cortisone or Neosporin to combat the inflammation and suppress the immune response causing the itching and rash.
  • If you can find it, use a powder developed specifically for prickly heat. Snake Brand sells a product here on Amazon. Also, some tropical areas’ local dispensaries have it available for sale

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