Baby Heat Rash: How to Help Prevent & Soothe It

Warm weather means more opportunities to enjoy time outdoors with your little one, but it can also bring common skin concerns like baby heat rash. The good news is that heat rash is usually harmless and often improves once your baby has cooled down.

Baby heat rash happens when sweat ducts become blocked, trapping sweat beneath the skin. It often appears as small red or raised spots, particularly around the neck, chest, back or skin folds where heat and moisture can build up.

In this guide, we'll explain what baby heat rash looks like, what causes it, simple ways to help keep your baby comfortable, how to reduce the risk during hot weather and when it's important to seek medical advice.

What does baby heat rash look like?

Baby heat rash (sometimes called baby prickly heat or newborn heat rash in younger babies) usually appears as clusters of tiny red, pink or raised spots. The affected skin may look irritated, and older babies may seem uncomfortable or itchy.

Heat rash is most likely to appear in areas where sweat becomes trapped, including:

• The neck

• The chest

• The back

• The shoulders

• Skin folds, such as under the arms or around the legs

• Areas covered by clothing

Some parents also notice baby heat rash on the face, particularly around the hairline or forehead during very warm weather, although it is more common on the neck and body.

Important: Heat rash can look similar to other baby rashes, including eczema, viral rashes or skin infections. If you’re unsure whether your baby has heat rash, speak to a GP, pharmacist, NHS 111 or another healthcare professional.

Quick guide: what heat rash looks like

You may notice:

✓ Small red or pink spots

✓ Tiny raised bumps

✓ Rash in warm, sweaty areas

✓ Skin that looks prickly or irritated

It's important to remember that heat rash can look similar to eczema, viral rashes and other skin conditions. If you're unsure what's causing your baby's rash or you're worried about how it looks, speak to your GP, pharmacist, NHS 111 or another healthcare professional for advice.

What causes heat rash in babies?

Heat rash develops when your baby's sweat ducts become blocked, preventing sweat from escaping normally. As sweat becomes trapped beneath the skin, small bumps and irritation can appear.

Several factors can make this more likely, including:

• Hot or humid weather

• Sweating during sleep

• Dressing your baby in too many layers

• Heavy or non-breathable clothing

• Warm prams, baby carriers or sleeping environments

• Heat and moisture collecting in skin folds

Because babies can't regulate their body temperature as efficiently as adults, they can become warm more quickly, especially during summer or in overheated indoor spaces.

How to soothe baby heat rash safely

If you think your baby has heat rash, the aim is simply to help them cool down and keep the affected skin comfortable.

You can help by:

• Moving your baby to a cool, shaded or well-ventilated area

• Removing unnecessary clothing layers

• Dressing them in loose, lightweight, breathable clothing

• Allowing the skin to air where practical

• Keeping the skin cool and dry

• Offering a lukewarm bath instead of a hot one

• Changing damp or sweaty clothing promptly

It's generally best to avoid applying heavy creams, oils or fragranced products unless a healthcare professional has advised you to use them, as these can sometimes trap more heat against the skin.

Although many parents search for how to treat baby heat rash, this guide focuses on simple comfort steps that may help reduce heat and sweating. Avoid using medicines, medicated creams or home remedies unless advised by a healthcare professional. If you're unsure whether your baby's rash is heat rash, or if it isn't improving, seek medical advice.

How to help prevent baby heat rash

While you can't always avoid heat rash, there are plenty of simple steps that can help reduce the chances of it developing during warmer weather.

Dress your baby in lightweight layers

Choose soft, lightweight, breathable clothing that allows air to circulate. Layers can be added or removed more easily as temperatures change throughout the day.

Choosing lightweight, breathable pieces such as organic cotton or bamboo bodysuits, rompers and summer sleepwear may help keep your baby comfortable in warm weather, allowing air to circulate and reducing excess heat build-up.

Avoid overheating

Babies don't always need as many layers as we think. During warm weather, check whether your baby seems too hot and remove layers if needed.

Keep your baby's environment cool

Where possible:

• Keep rooms well ventilated

• Use shade when outdoors

• Avoid spending long periods in very hot environments

When using a pram, avoid covering it with blankets or muslins, as this can trap heat and reduce airflow.

Take breaks from baby carriers

Baby carriers naturally keep your baby close to your body, which can make both of you feel warmer. During hot weather, taking regular breaks can help prevent excess heat from building up.

Change sweaty clothing

If your baby's clothes become damp from sweat, changing into dry clothing can help keep their skin comfortable.

Quick checklist

Dressing a baby in hot weather

Choosing the right clothing can make a big difference during warmer months.

Many babies are comfortable in a lightweight bodysuit, sleeveless or short-sleeved clothing, or a loose romper when temperatures are high. Indoors, they may need fewer layers than you expect.

Rather than checking your baby's hands or feet, feel their chest or the back of their neck to get a better idea of whether they're too warm.

For more detailed advice on choosing the right clothing for different temperatures, read our guide on How to Dress Your Baby in Summer. You can also explore summer baby clothes, including lightweight baby bodysuits, baby rompers and summer sleepwear made with soft, breathable fabrics for warmer days.

When should you get medical advice?

Although baby heat rash is usually mild, it's important to seek medical advice if:

• You're unsure whether the rash is heat rash

• The rash doesn't improve after your baby has cooled down

• The skin becomes swollen, painful or starts oozing, as these can be signs of an infection

• Your baby has a fever

• Your baby seems unusually sleepy, irritable or unwell

• There are signs of dehydration or overheating

• The rash spreads rapidly or you're concerned about your baby's symptoms

Most cases of baby heat rash are linked to warmth, sweating and blocked sweat ducts, so the main aim is to help your baby cool down and stay comfortable. Remove extra layers, keep their skin cool and dry, choose lightweight clothing and check regularly for signs they may be too hot. 

If the rash does not improve, your baby seems unwell or you’re unsure what has caused it, speak to a GP, pharmacist, NHS 111 or another healthcare professional.

FAQs

What does baby heat rash look like?

Baby heat rash usually appears as clusters of tiny red, pink or raised spots, often on the neck, chest, back or skin folds where sweat becomes trapped. It can look similar to other rashes, so seek advice if you’re unsure. 

Where does heat rash appear on babies?

Heat rash most commonly appears on areas where heat and sweat build up, such as the neck, chest, back, shoulders, skin folds and areas underneath clothing.

How long does baby heat rash last?

Heat rash usually gets better on its own after a few days once the skin is kept cool and sweating is reduced. If your baby’s rash does not improve after a few days, or you’re worried, speak to a GP, pharmacist, NHS 111 or another healthcare professional. See ‘NHS: Heat rash (prickly heat)’ for more on this. 

Can babies get heat rash on their face?

Yes. Babies can develop heat rash on the face, particularly around the forehead or hairline during hot weather, although it is more common on the neck and body.

How can I soothe baby heat rash? 

Move your baby somewhere cooler, remove unnecessary layers, keep their skin cool and dry, and dress them in loose, lightweight clothing. Avoid heavy creams, oils or medicated products unless advised by a healthcare professional. 

How can I help prevent baby heat rash?

Dress your baby in lightweight, breathable clothing, avoid overheating, keep rooms well ventilated, change damp or sweaty clothing promptly and avoid covering prams with blankets or muslins.

When should I speak to a doctor about a baby rash?

Seek medical advice if you’re unsure what has caused the rash, your baby seems unwell, has a fever, shows signs of dehydration or overheating, the rash appears infected, spreads quickly or does not improve.

Sources

• NHS: Heat rash (prickly heat)

• NHS: Rashes in babies and children

• The Lullaby Trust: Keeping babies cool in hot weather