Skip to main content
Common causes of summer rashes

What are the common causes of summer rashes?

Many people look forward to the warmer weather during the summer months. But higher temperatures or sun exposure can sometimes be bad news for skin, resulting in summer rashes. Skin rashes can be more common in hot or humid conditions - particularly heat rash - so if you or your child experience a new rash at this time of year there could be a number of different causes.

Continue reading below

What causes heat rash?

One of the most common rashes experienced during the warmer months is heat rash - this occurs when the skin's sweat glands are blocked, or can be a result of excess sweat due to overheating or physical activity.

"A heat rash occurs when the sweat gland pores become blocked and sweat is unable to evaporate from the surface of the skin. This results in red bumps or an itchy skin sensation," explains Dr Zainab, dermatologist from Omniya Clinic.

How to treat heat rash

Luckily, while heat rash can be itchy and uncomfortable, keeping the skin cool should relieve symptoms and the rash will usually resolve on its own. "Heat rashes are self-limiting and should resolve within 3-4 days," says Zainab. However, if you or your child develop fever or chills, or the rash becomes painful, it's a good idea to consult your GP or pharmacist.

Is the sun good for eczema?

If you or your child already suffer from eczema or psoriasis, the good news is that sunlight can often help to improve the condition. "Many common inflammatory conditions like eczema and psoriasis can clear up in the sun," agrees Ophelia Veraitch, consultant dermatologist at Cranley Clinic.

However, overheating or excess sun exposure can cause eczema and psoriasis to flare up, often due to excess perspiration. In addition, certain sunscreens may cause a reaction in sensitive skin.

If you or your child suffer from an inflammatory skin condition, enjoy outdoor fun but try to limit direct sun exposure. Speak to your pharmacist about the best sunscreen solution for your skin.

Continue reading below

What is photosensitivity caused by?

Some individuals experience an extreme reaction when skin is exposed to the sun due to photosensitivity. "Many people suffer from skin sensitivity and skin reactions to sunlight. There are several different skin diseases that can cause these reactions," explains Veraitch. For example, autoimmune diseases such as lupus.

Some skincare products may also make you more susceptible to sun damage - for example, certain anti-ageing creams, or the acne treatment benzoyl peroxide.

"One of the key features that helps a dermatologist work out the cause of photosensitivity is how long after sun exposure the skin problem begins. If you experience pain or itch within seconds or minutes of exposure to the sun, the reaction could be caused by medication-induced light sensitivity or a solar urticaria. If the itchy rash develops within hours or days of exposure to the sun this could be caused by rarer conditions such as lupus, a light-sensitive eczema or actinic prurigo (a chronic inflammatory skin condition)," says Veraitch.

If you're aware that you have a condition that flares up in the sun, extra caution is advised. Wear loose, cotton clothing, seek out the shade and take advice from your pharmacist or doctor about skincare products.

Insect bite reactions

Most insect stings or bites cause inflammation around the site, and can be itchy as they heal. With insects being more prevalent in the summer months, insect bites can be a common cause of summer rashes. This type of reaction can usually be dealt with easily at home, although it may be uncomfortable.

How to treat an insect bite

Keep the affected area clean and apply a cool cloth or ice pack to reduce swelling. You may also wish to speak to your pharmacist about creams to limit symptoms and promote healing. If your skin develops a blister, avoid bursting this as this may lead to infection.

Bites and stings are usually uncomfortable but not harmful. However, if you are worried about a bite or sting, speak to your pharmacist or call NHS 111 for advice. You should also seek medical attention if you are stung on a sensitive area, such as close to your eye.

Insect bites and stings may sometimes become infected, so if you experience more severe discomfort or swelling, it's important to seek advice.

Allergic reactions to insect bites or stings

Some individuals may experience an allergic reaction to an insect bite or sting. The most severe of these is anaphylaxis in reaction to an insect sting (usually a bee or wasp sting in the UK), which can be life-threatening. If you or your child begin to experience excess swelling in the face or throat, feel dizzy, develop any breathing problems or lose consciousness, emergency services should be called.

If you do have one anaphylactic reaction to an insect sting, you must try to avoid ever getting stung again. You must also carry an adrenaline auto-injector to treat yourself as soon as you're stung and ensure that you and others know what steps to take in an emergency.

While it can be hard to avoid insects during the summer months, insect repellent may help to prevent bites and stings.

Continue reading below

Allergies and plant reactions

If you suffer from allergy to pollen, you may experience allergic symptoms such as hay fever. But such allergies can also affect your skin, resulting in summer rashes. If you suffer from allergies, make sure you take any prescribed medication. If you develop skin irritation, or hay fever symptoms for the first time, speak to your pharmacist for advice.

In addition, "certain plants - for example, poison ivy and poison oak, can make skin more sensitive to sunlight and cause redness, swelling and blisters to develop," explains Zainab.

Wearing gloves for gardening and avoiding contact with any known allergens should help to reduce the instance of allergic reactions.

When should you seek help for summer rashes like heat rash?

Although conditions like heat rash are more common in the summer months, illnesses that may cause rashes are still around throughout the year. If you or your child develop a fever or chills, or are feeling generally unwell, it's important to seek medical advice via your pharmacist or 111, or, if the symptoms are severe and include breathlessness or facial swelling, by calling 999.

Article history

The information on this page is peer reviewed by qualified clinicians.

symptom checker

Feeling unwell?

Assess your symptoms online for free