Erythema Multiforme

Overview

Erythema multiforme (say: er-uh-THEE-muh mul-tih-FOR-may) is a skin reaction that causes a rash, often with raised red or pink patches that look like small targets or bullseyes. It is not an infection you can pass to other people, and it is not a sign of poor hygiene. It is your immune system reacting to something — most often a common infection, and sometimes a medicine. Most cases are mild and settle down within a few weeks, but a small number of people get a more serious form that needs urgent medical care.

Erythema multiforme is uncommon but not rare. General practice doctors see it from time to time, and it is seen more often in young adults. The mild form is much more common than the serious form.

It can affect anyone, but it is most often seen in people aged 20 to 40. Children can get it too, usually after an infection. Some people have repeated episodes, especially if cold sores keep coming back.

Symptoms

Common symptoms

• A rash of round, target-like spots — usually pink or red, sometimes with a darker or blistered centre
• Spots on the backs of hands, palms, forearms, tops of feet, shins, and sometimes knees and elbows
• The rash often appears on both sides of the body in a similar way
• Spots may be flat or slightly raised, and may join together into larger patches
• Itching, burning or tenderness in the rash
• Feeling tired, achy or generally unwell for a few days before the rash appears
• A mild fever in some people
• Sores or blisters inside the mouth in some cases, which can make eating uncomfortable
• Sore, red or watery eyes in some cases

Symptoms in children

• Often starts with a fever, cough, sore throat or general 'cold' symptoms a few days before the rash
• The rash may be more widespread and less clearly 'target-shaped' than in adults
• Mouth sores can be prominent and may make a child reluctant to eat or drink
• Irritability and tiredness are common
• Children can become dehydrated quickly if mouth sores stop them drinking — watch for fewer wet nappies or trips to the toilet

Symptoms in older adults

• Medicines are a more likely trigger in this age group, so a recent new prescription should always be reviewed
• Symptoms may be more severe, and recovery can take longer
• Dehydration and skin infection are bigger risks, especially if there are mouth sores or broken skin
• A rash in an older adult who also feels unwell should be checked the same day

Causes

Main causes

• Infections — the cold sore virus (herpes simplex) is the most common trigger worldwide; other infections such as a chest infection called mycoplasma, and various viral illnesses, can also set it off
• Medicines — some antibiotics, some pain relievers, and some medicines used for epilepsy or gout are known triggers
• Vaccines — rarely, a reaction can follow vaccination, but this is uncommon and is not a reason to avoid recommended vaccines
• Underlying illness — occasionally it is linked to another health condition or to a weakened immune system
• No clear cause — in some people, no trigger is ever found

Risk factors

• Having repeated cold sores or another herpes infection
• A recent infection, especially a respiratory or viral illness
• Starting a new medicine in the two weeks before the rash
• Having a weakened immune system
• A personal or family tendency to react strongly to infections
• Previous episodes of erythema multiforme — it can come back, especially with repeated cold sores

When to see a doctor

See a doctor urgently if:

• Any blistering or peeling skin
• Sores in the mouth, eyes or genital area
• Fever with a spreading rash
• Red or painful eyes
• A rash that started soon after a new medicine
• Feeling very unwell, or unable to drink because of mouth sores
• Breathing difficulty or swelling of the face or throat — call your local emergency number immediately

Book a routine appointment if:

• A new target-shaped rash, even if you feel well
• A rash that is not settling after a week
• Repeated episodes of the same rash
• You want to know which medicines to avoid in future
• You are unsure whether the rash needs checking

Diagnosis

There is no single test for erythema multiforme. A doctor usually recognises it from the pattern of the rash and by asking about recent infections, cold sores, new medicines and how you have been feeling. They will also check your mouth and eyes and look at how much skin is involved. Because a more serious skin reaction can look similar at first, the doctor may want you seen again or referred to a skin specialist if anything seems unusual.

Tests that may be done

• A careful skin examination, including the mouth, eyes and genital area
• A review of all medicines taken in the past few weeks, including ones bought without a prescription
• Blood tests to check general health and look for signs of infection
• A swab or blood test for herpes simplex if a cold sore trigger is suspected
• A small skin sample (biopsy) in unusual or severe cases
• Chest X-ray or other tests if a mycoplasma infection is suspected
• Eye examination by a specialist if the eyes are involved

What to expect at your appointment

The appointment is mostly a conversation and a look at your skin. You may be asked to undress down to your underwear so the doctor can see the whole rash. Bring a list of every medicine you take, including supplements and anything you bought yourself, and note the dates you started them. If a biopsy is needed, a small area of skin is numbed first, and results usually take one to two weeks. You should be told what to watch for and when to come back.

Treatment

Treatment depends on how mild or severe the reaction is and on what triggered it. The single most important step is to remove the trigger where possible — for example, stopping a suspected medicine under medical guidance, or treating an infection. Most mild cases need only supportive care: rest, plenty of fluids, gentle skin care and something for pain or itch. More troublesome cases may need medicines prescribed by a doctor to calm the reaction or treat the underlying infection.

Self-care at home

• Rest and give your body time to recover — tiredness is common in the first week
• Drink plenty of fluids, especially if you have mouth sores; sip often through a straw if it helps
• Choose soft, cool, bland foods if your mouth is sore — soups, yoghurt, mashed food, smoothies
• Avoid salty, spicy, acidic or very hot foods and drinks while your mouth heals
• Keep the skin clean and gently moisturised; pat dry rather than rubbing
• Avoid scratching, and keep nails short
• Try cool compresses or a cool bath to ease itching and burning
• Wear loose, soft clothing and avoid tight waistbands or rough fabrics over the rash
• Stay out of strong sun and protect your skin — sun can make the rash feel worse
• Ask your pharmacist before taking any painkiller or anti-itch product, since some medicines can trigger this reaction

Medical treatments

Doctors treat erythema multiforme in a stepwise way. First, any suspected triggering medicine is reviewed and usually stopped — never stop a prescribed medicine on your own; always check with the prescriber or pharmacist first. If an infection is found, such as a herpes infection or a chest infection, that infection is treated. For the rash itself, doctors may prescribe creams or ointments to reduce inflammation and help healing, mouth rinses or gels to make eating more comfortable, and sometimes short courses of medicines taken by mouth to calm the immune reaction or ease itch and pain. In more serious cases, treatment is given in hospital with fluids, wound care, eye care and close monitoring. Which approach is right for you depends on your age, your other health conditions, how much skin is involved and what triggered the reaction — your doctor will explain the options and why they are recommending one.

When is surgery considered?

Surgery is not part of treating erythema multiforme. Skin that has been damaged may need specialist wound care in severe cases, but this is not an operation.

Living with this condition

In the first week or two, plan for a slower pace. The rash can look alarming, but it usually fades gradually — spots may flatten, turn brownish or leave faint marks that lighten over weeks to months. Keep taking any regular medicines as prescribed unless your doctor tells you to change them, and write down any medicine you have been told to avoid so you can tell every future prescriber, dentist and pharmacist. If cold sores keep triggering episodes, talk to your doctor about ways to reduce them.

Lifestyle tips

• Keep a simple record of medicines you start and any reaction that follows, with dates
• Tell every healthcare professional about your reaction, including pharmacists and dentists
• Ask your pharmacist to flag the reaction in your medication record
• Get enough sleep and eat well while you recover — your body is doing a lot of healing
• Avoid known triggers, including any medicine you have been advised to stop
• Manage stress where you can; it will not cause the rash but it affects how well you cope
• Protect your skin from strong sun and use gentle, unperfumed products

Diet and exercise

There is no special diet for erythema multiforme, but good nutrition and fluids help healing. While your mouth is sore, soft, cool, bland foods are easiest — soups, yoghurt, scrambled eggs, mashed vegetables, smoothies. Avoid very hot, spicy, salty or acidic foods, and fizzy drinks. Once you feel better, return to your normal balanced diet. Take gentle exercise such as short walks when you feel up to it, but rest if you are tired or feverish, and avoid activities that rub or irritate the rash.

Mental health and emotional wellbeing

A visible rash can be upsetting. Some people feel self-conscious, worried about what others think, or anxious that the rash is something worse. Sleep can be disturbed by itching, and mouth sores can make eating with others uncomfortable. These feelings are understandable and usually ease as the rash fades. Tell your doctor if low mood, worry or sleep problems are building up — support is available, and you do not have to cope alone. If you ever feel hopeless or have thoughts of harming yourself, please reach out for crisis support straight away — contact your local emergency number or a local crisis line, or speak to someone you trust and ask them to stay with you.

Prevention

You cannot always prevent erythema multiforme, but you can lower the chance of a repeat episode. If a medicine was the trigger, avoiding that medicine — and telling every prescriber about it — is the single most effective step. If cold sores are the trigger, treating cold sores early and discussing ways to reduce how often they come back can help. If an infection was the trigger, that infection can be treated. Sometimes no cause is found, and then prevention focuses on recognising the early signs and getting checked quickly.

Vaccines

There is no vaccine for erythema multiforme. Vaccines are only very rarely a trigger, and having had this reaction is not generally a reason to skip routine immunisations. Any decision about future vaccines should be made with your doctor, who can weigh up the very small risk against the real protection vaccines offer.

Screening programmes

There is no screening test for erythema multiforme. If you have had it before, the best 'screening' is simply knowing the early signs and being checked quickly if the rash returns, especially if you also feel unwell or get mouth or eye sores.

Complications

If left untreated

• Dehydration from not drinking enough because of mouth sores — a particular risk in children and older adults
• A skin infection where blisters or broken skin allow bacteria in
• Eye problems if the eyes are involved and not checked and treated
• Scarring or lasting dark or pale marks on the skin in some people
• Recurring episodes, especially when cold sores keep coming back
• In rare cases, the reaction can become a more serious form with widespread blistering and peeling skin — this is why warning signs matter

Long-term outlook

The outlook is good for most people. The common form usually clears in two to four weeks, and the skin generally returns to normal, though faint marks may take longer to fade. Some people do have repeat episodes, particularly if triggered by cold sores, and knowing your trigger makes a real difference. Serious reactions are uncommon and are treated in hospital with good supportive care. The important thing is to have a first episode checked, learn your trigger, and know the warning signs so you can act quickly if they ever appear.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.