Because the eruption is transient and self-limiting, no treatment is indicated.

With no particular affinity to any particular ethnic group, seen in all age groups and equally amongst males and females, the precise prevalence is not known.

Erythema multiforme is frequently self-limiting and requires no treatment. The appropriateness of glucocorticoid therapy can be uncertain, because it is difficult to determine if the course will be a resolving one.

No treatment is usually needed as they usually go away anywhere from months to years. The lesions may last from anywhere between 4 weeks to 34 years with an average duration of 11 months. If caused by an underlying disease or malignancy, then treating and removing the disease or malignancy will stop the lesions. It usually doesn't require treatment, but topical corticosteroids may be helpful in reducing redness, swelling and itchiness.

Some supported and not supported methods of having an effect on EAC include:

- Photosensitive so it can be moved/reduced with appropriate sunlight.

- Vitamin D

- Immune system - hence it will increase in size/number when the immune system is low or overloaded.

- Hormone Drugs

- Disulone

- Stress reduction

- Topical calcipotriol - a topical vitamin D derivative has been known to be beneficial

Some sources claim that diaper rash is more common with cloth diapers. Others claim the material of the diaper is relevant insofar as it can wick and keep moisture away from the baby's skin, and preventing secondary "Candida" infection. However, there may not be enough data from good-quality, randomized controlled trials to support or refute disposable diaper use thus far. Furthermore, the effect of non-biodegradable diapers on the environment is a concerning matter for public policy.

The cause of erythema toxicum is thought to be an activation of the immune system. Some neonates are more sensitive than others and develop erythematous spots all over the body. Another theory is hypersensitivity to detergents in bedsheets and clothing is sometimes suspected, but the connection remains unproven.

It is thought to be a benign condition that causes no discomfort to the infant. The rash will generally disappear spontaneously in about 2 weeks.

Both lyme disease and STARI can be treated with antibiotics, particularly doxycyclin.

A full recovery is expected with treatment. Recurrent id reactions are frequently due to inadequate treatment of the primary infection or dermatitis and often the cause of recurrence is unknown.

Erythema (redness) multiforme (EM) is usually a reaction of the skin and mucous membranes that occurs suddenly. It appears as a symmetrical rash and may include the mucous membrane lesions. This means that the body is sensitive to something that causes the skin and mucous membranes to react. The more common mild form is refer to as EM minor. It consists of a skin rash that involve no more than one mucosal surface. The sudden onset will progress rapidly as symmetrical lesions with circular color changes in some or all of the lesions. Rash will spread towards center or trunk of the body. Evenly distributed bumps on the skin become classic iris or target lesions. They have bright red borders and small white bumps in the center.

The cause of EM appears to be a highly sensitive reaction that can be triggered by a variety of causes. The causes can include bacterial, viral or chemical products, such as antibiotics – specifically penicillins or cephalosporins. This reaction is an allergic reaction and is in no way contagious.

Erythema multiforme minus is sometimes divided into papular and vesiulobullous forms.

The most effective treatment, although not the most practical one, is to discontinue use of diapers, allowing the affected skin to air out. Another option is simply to increase the frequency of diaper changing. Thorough drying of the skin before diapering is a good preventive measure because it is the excess moisture, either from urine and feces or from sweating, that sets the conditions for a diaper rash to occur.

Many suspected aetiologic factors have been reported to cause EM.

- Infections: Bacterial (including Bacillus Calmette-Guérin (BCG) vaccination, haemolytic "Streptococci", legionellosis, leprosy, "Neisseria meningitidis, Mycobacterium, "Pneumococcus, "Salmonella" species, "Staphylococcus" species, "Mycoplasma pneumoniae), "Chlamydial.

- Fungal (Coccidioides immitis)

- Parasitic ("Trichomonas" species, "Toxoplasma gondii), "

- Viral (especially Herpes simplex)

- Drug reactions, most commonly to: antibiotics (including, sulphonamides, penicillin), anticonvulsants (phenytoin, barbiturates), aspirin, antituberculoids, and allopurinol and many others.

- Physical factors: radiotherapy, cold, sunlight

- Others: collagen diseases, vasculitides, non-Hodgkin lymphoma, leukaemia, multiple myeloma, myeloid metaplasia, polycythemia

EM minor is regarded as being triggered by HSV in almost all cases. A herpetic aetiology also accounts for 55% of cases of EM major. Among the other infections, "Mycoplasma" infection appears to be a common cause.

Herpes simplex virus suppression and even prophylaxis (with acyclovir) has been shown to prevent recurrent erythema multiforme eruption.

Erythema nodosum is self-limiting and usually resolves itself within 3–6 weeks. A recurring form does exist, and in children it is attributed to repeated infections with streptococcus. Treatment should focus on the underlying cause. Symptoms can be treated with bedrest, leg elevation, compressive bandages, wet dressings, and nonsteroidal anti-inflammatory agents (NSAIDs). NSAIDs are usually more effective at the onset of EN versus with chronic disease.

Potassium iodide can be used for persistent lesions whose cause remains unknown. Corticosteroids and colchicine can be used in severe refractory cases. Thalidomide has been used successfully in the treatment of Erythema nodosum leprosum, and it was approved by the U.S. FDA for this use in July 1998.

Erythema marginatum is a type of erythema (redness of the skin or mucous membranes) involving pink rings on the torso and inner surfaces of the limbs which come and go for as long as several months. It is found primarily on extensor surfaces.

An association with bradykinin has been proposed in the case of hereditary angioedema.

It can be caused by infection, massage, electrical treatment, acne medication, allergies, exercise, solar radiation (sunburn), cutaneous radiation syndrome, mercury toxicity, blister agents, niacin administration, or waxing and tweezing of the hairs—any of which can cause the capillaries to dilate, resulting in redness. Erythema is a common side effect of radiotherapy treatment due to patient exposure to ionizing radiation.

Erythema (from the Greek "erythros", meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not associated with pathology include nervous blushes.

Southern tick-associated rash illness (STARI) produces a similar rash pattern although it develops more quickly and is smaller. This erythema is also sometimes called erythema migrans or EM. The associated infectious agent has not been determined. Antibiotic treatment resolves the illness quickly.

Erythema ab igne was once commonly seen in the elderly who stood or sat closely to open fires or electric heaters; however, erythema ab igne has been reported in both young and elderly individuals. Women have a higher incidence of erythema ab igne than men. Although wide use of central heating has reduced the overall incidence of erythema ab igne, it is still sometimes found in people exposed to heat from other sources such as heating pads, space heaters, hot water bottles, and electronic devices.

Erythema nodosum is the most common form of panniculitis. It is most common in the ages of 20–30, and affects women 3–6 times more than men.

About 15 percent of patients with inflammatory bowel disease develop erythema nodosum.

Palmar erythema has no specific treatment. Management is based on the underlying cause. When its cause is treated then patients get relief. If it is attributable to a particular drug then the drug should be withdrawn.

Discontinuing contact with the heat source is the initial treatment of erythema ab igne. If the area is only mildly affected with slight redness, the condition may resolve itself in a few months. If the condition is severe and the skin pigmented and atrophic, resolution is unlikely. In this case, there is a possibility that a squamous cell carcinoma or a neuroendocrine carcinoma such as a Merkel cell carcinoma may form. If there is a persistent sore that does not heal or a growing lump within the rash, a skin biopsy should be performed to rule out the possibility of skin cancer. If the erythema ab igne lesions demonstrate pre-cancerous changes, the use of 5-fluorouracil cream has been recommended. Abnormally pigmented skin may persist for years. Treatment with topical tretinoin or laser may improve the appearance.

Some sources distinguish between the following:

- "Erythema marginatum rheumaticum"

- "Erythema marginatum perstans"

The medieval "Bald's Leechbook" recommended treating chilblains with a mix of eggs, wine, and fennel root.

A common tradition of Hispanic America recommends warm garlic on the chilblains.

Erythema multiforme major (also known as "erythema multiforme majus") is a form of rash with skin loss or epidermal detachment.

The term "erythema multiforme majus" is sometimes used to imply a bullous (blistering) presentation.

According to some sources, there are two conditions included on a spectrum of this same disease process:

- Stevens–Johnson syndrome (SJS)

- Toxic epidermal necrolysis (TEN) which described by Alan Lyell and previously called Lyell syndrome[5].

In this view, EM major, SJS and TEN are considered a single condition, distinguished by degree of epidermal detachment.

However, a consensus classification separates erythema multiforme minor, erythema multiforme major, and SJS/TEN as three separate entities.

Erythema anulare centrifugum (EAC), also known as deep gyrate erythema, erythema perstans, palpable migrating erythema and superficial gyrate erythema, is a descriptive term for a class of skin lesion presenting redness (erythema) in a ring form ("anulare") that spreads from a center ("centrifugum"). It was first described by Darier in 1916. Many different terms have been used to classify these types of lesions and it is still controversial on what exactly defines EAC. Some of the types include annular erythema (deep and superficial), erythema perstans, erythema gyratum perstans, erythema gyratum repens, darier erythema (deep gyrate erythema) and erythema figuratum perstans.

A single case report suggested that oral dapsone may be useful for prevention. However, the efficacy of oral dapsone as prevention has not been demonstrated very clearly until now.