Skin rashes can vary a lot in their appearances and the symptoms that may accompany them, which can make them tricky to diagnose.

Most rashes are not life-threatening; however, some rashes can be a sign of a more serious health issue. See your doctor if any of the following occur as well as the rash:

• Fever;
• swollen lymph nodes in the armpit, groin, or neck;
• the rash is all over your body;
• the rash begins to blister;
• the rash appears suddenly and spreads rapidly;
• the rash is painful; or
• there is a chance the rash is infected – i.e. if the skin is swollen, weeping, hot to touch, or if there are red streaks visible on the skin.

Call 000 if the rash is accompanied by a severe headache, neck stiffness and fever, or vomiting and nausea.

Heat Rash

This rash is caused when sweat ducts become inflamed and blocked due to high humidity and heat. It is relatively harmless but very itchy, and forms where sweat tends to collect, such as the back, crooks of knees and elbows, under the breasts and in the armpits. It appears as tiny red spots, with the area of affected skin looking red and mildly swollen, with an itchy, prickling feeling.

Hives (Urticaria)

Hives is a rash that can occur on any area of the body but is usually found on the arms, throat, torso, and legs. They can be triggered by a number of things, including stress, contact with animals or plants, allergic reactions to medications or foods, and insect stings.

Hives appear as raised circular weals that look somewhat like mosquito bites. They are usually red at the outer rim and white at the centre and appear in batches that are present for around two to four hours. Acute urticaria rashes can last for days or even weeks.

Insect Stings

These happen when an insect punctures the skin, and leaves behind venom, saliva, or faeces in the skin, along with its ‘sting’. Initially, a sting will feel painful for around an hour and be accompanied by an intense burning sensation.

Redness is usually visible in the skin around the sting site, and some swelling of the skin in the area is common. Stings usually resolve in around two days.

Shingles

Shingles is a painful blistering rash that is caused by the varicella-zoster virus. The rash typically appears on a single side of the body or face, and starts out looking red, and then breaks out in small, fluid-filled blisters. It often has the shape of a belt from the midline on one side of the body, due to the virus spreading down the nerves that branch from the spinal cord.

If you suspect you have shingles, see your doctor immediately, as antiviral treatment is most effective if it’s commenced within three days of the rash appearing. A vaccine is available for people over fifty years of age. Talk to your doctor if you think this vaccination is suitable for you.

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Medical information published on this website is of a general nature only and not intended to be a substitute for informed healthcare professional advice or clinical care. If you have specific healthcare concerns or issues you should consult with a qualified health care professional such as your own GP.