Alphabetical List of Common Rashes and Their Causes
A Look at the Presentation, Causes, and Course of 22 Different Rashes
Medically reviewed by Leah Ansell, MDFact checked by Nick Blackmer
Skin rashes appear on the body as irritated or swollen areas covered in skin lesions that may be itchy, painful, dry, discolored, or include a range of other symptoms depending on the type of rash.
Rashes can have various causes, including allergies, irritation, viruses, bacteria, and more. Treatments depend on the type of rash.
This article discusses 22 different types of skin rash, what they look like, what causes them, and how they are treated.
Features of Skin Rashes
The term “dermatitis” is used to describe a simple rash. Here are some other terms used to describe the common characteristics of different types of rashes.
Bulla (plural bullae): A fluid-filled sac that is greater than 1 cm (about 0.4 inches) in diameter
Comedone: A plug made of skin oils and keratinous material found in a follicle; an open comedone is black (“blackhead”) and a closed comedone is white (“whitehead”)
Lichenification: Thick or leathery appearance to the skin
Macule: A flat lesion that is less than 1 cm in diameter
Nodule: Solid, elevated lesion between 1 cm and 5 cm (about 2 inches) in diameter
Papule: A solid “bump” that is less than 1 cm in diameter
Papulosquamous: A lesion consisting of papules and plaques with superficial scaling
Patch: A flat lesion that is greater than 1 cm in diameter
Petechia: A pinpoint purple or red spot caused by bleeding under the skin
Plaque: A raised lesion that resembles a plateau and is greater than 1 cm in diameter; often, a plaque is made up of a convergence of smaller papules
Purpura: Purple spots on the skin caused by bleeding under the skin
Pustule: An elevated blister of any size filled with pus
Vesicle: A fluid-filled sac that is less than 1 cm in diameter
Wheal: An inflamed plaque or papule accompanied by swelling and itchiness
Acne Vulgaris
Clinical presentation: Pustules, papules, comedones, nodules on face, chest, and back
Principal age group(s): Adolescents
Cause: Associated with hormone changes of puberty. Severe acne runs in families. Finding a link to food is an active area of interest.
Course: Acne typically goes away during adulthood, but resultant scarring and pitting from acute acne can be lifelong.
Acne vulgaris, or acne, is so common that mild cases have been termed “physiologic,” and mild acne is not considered a disease or illness.
Here are the steps in acne formation:
Overgrowth of follicles (comedones)
Excess sebum production
Inflammation
Infection with the bacteria Propionibacterium acnes
Acne often requires treatment by a physician to minimize discomfort and reduce the risk of long-term scarring. It should be treated early to help reduce its ongoing severity.
Acne is often treated using various medications. Cleansing is also important. Common treatment options include retinoid combinations applied to the skin, antibiotics, and benzoyl peroxide. Some over-the-counter benzoyl peroxide products also include salicylic acid to exfoliate the skin and clean pores.
Atopic Dermatitis (Atopic Eczema)
Clinical presentation: Itchy papules, lichenification, rash on face and arms
Principal age group(s): Infants, young children
Cause: Associated with allergies
Course: Chronic and relapsing, some children outgrow it
Atopic dermatitis is an itchy skin condition that runs in families. Mild cases of atopic dermatitis can be treated with topical steroids (glucocorticoids), which are available over the counter.
More severe cases may be treated with tacrolimus and pimecrolimus, which are immunomodulators prescribed by a physician. People who have atopic dermatitis should avoid allergens that trigger the conditions, such as detergents and animal dander.
Bullous Pemphigoid
Clinical presentation: Bullae
Principal age group(s): Older adults
Cause: Autoimmune
Course: Waxes or wanes, remission in many
Bullous pemphigoid is a rare, inflammatory autoimmune disease that results in blistering of the skin and mucous membranes in older adults. Treatment of bullous pemphigoid is complex and requires input from various specialists, including dermatologists, ophthalmologists, and primary care physicians. More severe cases may require treatment with systemic corticosteroids.
Dermatitis Herpetiformis
Clinical presentation: Papules and vesicles on the elbows, knees, buttocks, back, or scalp
Principal age group(s): People between 30 and 40 years old
Course: Long-term but can go into remission; remission is defined as lasting two-plus years
Dermatitis herpetiformis is an itchy rash that appears in a symmetrical pattern over the elbows, knees, buttocks, back, or scalp. The bumps and blisters of this condition resemble infection with the herpes virus. It is more common in men and usually affects people of Northern European descent. Dermatitis herpetiformis occurs mostly in people with celiac disease, and symptoms usually clear with the adoption of a gluten-free diet.
Dermatitis Neglecta
Clinical presentation: Hyperpigmented papules and plaques with a warty appearance
Principal age group(s): All age groups, but most prevalent in children
Cause: Failure to clean or scrub parts of the body
Course: Resolves once the lesions are removed and hygiene is re-established
Dermatosis neglecta is a skin condition that occurs when a person neglects to regularly clean a part of their body. It can happen as a result of intentional neglect, or when someone has a medical condition that makes it hard to clean a particular body part.
People with this condition have lesions that are dark in color and tend to have a warty appearance. They are caused by an accumulation of dirt, sweat, sebum, keratin, and dead skin cells. They can be removed with exfoliation and a cleansing agent such as alcohol.
Erythema Multiforme
Clinical presentation: Target-shaped lesions
Principal age group(s): Young adults
Cause: Allergic reaction
Course: Transient; one to two weeks
Erythema multiforme is a short-lasting inflammatory skin condition. The rash appears as red welts and affects the eyes, mouth, and other mucosal surfaces. The rash of erythema multiforme takes the form of concentric circles or target lesions.
This condition is a type of allergic reaction and can appear secondary to herpes infection, fungal infections, streptococcal infection, or tuberculosis. Erythema multiforme can also result from chemicals or medications, such as NSAIDs, allopurinol, and certain antibiotics. Finally, erythema multiforme can accompany inflammatory bowel disease and lupus.
There are two types of erythema multiforme. Erythema multiforme minor results in mild illness that affects only the skin and sometimes causes mouth sores. Erythema multiforme major starts with systemic symptoms that affect the entire body, such as achiness in the joints and fevers. People with erythema multiforme major may have more serious sores that affect the genitals, airways, gut, or eyes.
These other symptoms can also accompany the rash in erythema multiforme major:
Fever
Malaise
Achiness
Itchy skin
Achy joints
Typically, erythema multiforme goes away on its own without treatment. Certain treatments can be administered, including steroids, antihistamines, antibiotics, moist compresses, and pain medicines. It’s important to keep lesions clean and maintain good personal hygiene to limit the risk of secondary infection.
Related: What Is Erythema?
Erythema Nodosum
Clinical presentation: Painful, reddened plaques with jagged or irregular edges, usually found at the level of the shins, calves, arms, and thighs; over weeks, the plaques flatten out and take on the appearance of bruises
Principal age group(s): All ages
Cause: In about half the cases, the cause is unknown. Other causes include infections and medications, such as antibiotics. Erythema nodosum can also occur during pregnancy, leukemia, sarcoidosis, and rheumatic fever.
Course: Uncomfortable, typically resolves after six weeks
Erythema nodosum is a form of panniculitis, an inflammation of the layer of fat underneath the skin. The skin lesions first begin as flat, firm, inflamed lumps, about one inch in diameter. These painful lumps may become purplish after a few days. After several weeks, the lesions become brownish, flat patches.
In addition to skin lesions, erythema nodosum can also cause more general symptoms, including fever, general malaise, achiness, and swelling. Treatment depends on the underlying cause and can include either treatment of the infection or disease or discontinuation of a drug. Other treatments include steroids, NSAIDs, and/or warm or cold compresses.
Folliculitis
Clinical presentation: Infected pustules mostly affecting the face, scalp, buttocks, extremities, groin, and torso
Principal age group(s): All ages
Cause: Bacterial, viral, or fungal
Course: Typically resolves
Folliculitis is an inflammation of the hair follicle. It can be on the surface and affect only the upper hair follicle, or it can affect the entire depth of the follicle. Deeper infection can lead to boils. Folliculitis can be caused by bacteria, viruses, or fungi.
Folliculitis can also be caused by noninfectious agents such as tight-fitting clothing, topical steroids, ointments, makeup, and lotions. Treatment is determined by the cause and may include antiviral medication, antibiotics, or antifungals.
Herpes
Clinical presentation: Cold sores, vesicles, and ulcers; in children, inflammation of the lining of the mouth and gums (i.e., gingivostomatitis)
Principal age group(s): All ages
Cause: Viral
Course: Typically resolves but will usually recur
The World Health Organization (WHO) estimates that 3.7 billion people younger than 50 years old are infected with the herpes simplex virus (HSV-1). The HSV-1 virus is spread through oral contact. Although cold sores can be unsightly and uncomfortable, they cause no other symptoms. Antiviral ointments or creams can relieve the burning, itching, and discomfort associated with cold sores.
Infection with herpes simplex virus type 2 (HSV-2) causes genital herpes. Genital herpes is sexually transmitted. However, HSV-2 can also cause cold sores. The WHO estimates that 13 percent of the world’s population is infected with genital herpes.
Herpes Zoster (Shingles)
Clinical presentation: Redness, vesicles
Principal age group(s): Adults 50 years or older, adults with weakened immune systems
Cause: Varicella zoster virus reactivation
Course: Two to three weeks
Herpes zoster, or shingles, is a painful skin rash that is caused by the varicella-zoster virus. Initial infection with the virus causes chickenpox, usually in childhood. After the chickenpox clears up, the virus stays dormant in nerve cells for many years. Reactivation of the virus produces shingles.
With herpes zoster, pain precedes the rash. The rash appears on one side of the torso or face and may be accompanied by symptoms such as headache, sensitivity to light, and malaise.
There is no cure for herpes zoster. Treatments include pain medications, steroids, antiviral drugs, and antihistamines. There is a vaccine for herpes zoster, which is different from the chickenpox vaccine. The vaccine, called Shingrix, is approved for all adults 50 and over and for adults 19 years and older who have weakened immune systems. It reduces the risk of shingles and complications of the illness, such as lingering chronic pain (postherpetic neuralgia).
Ichthyosis Vulgaris
Clinical presentation: Dry, scaly skin that may be itchy and flaky
Principal age group(s): Begins in childhood
Cause: Usually genetic, though it is possible to develop the condition in adulthood
Course: Usually resolves during adulthood but may return with older age
Most people who have ichthyosis vulgaris have a gene mutation that causes a change in the normal growing and shedding cycle of the skin. This can cause skin cells to build up, producing itchy, flaky scales. There is no cure for the condition, but it can be managed.
Treatment usually involves applying moisturizers to the skin after bathing. Moisturizers that contain lactic acid, urea, or salicylic acid can help promote normal shedding of the skin.
Impetigo
Clinical presentation: Pustules, vesicles, honey-colored crusting, reddened areas of skin erosion
Principal age group(s): Children between 2 and 6 years old
Cause: Bacterial
Course: Resolution after a few days
Impetigo is the most superficial type of skin infection. Impetigo is caused by Staphylococcus aureus or Streptococcus pyogenes bacteria. Impetigo is contagious and is spread among members of the same household. Impetigo is common in areas where people have little access to soap and clean water, such as in developing nations. Impetigo is also common among homeless people.
Both topical and oral antibiotics can be used to treat impetigo. If the impetigo is caused by methicillin-resistant S. aureus (MRSA), a drug-resistant bacteria, then oral antibiotics are needed. The best way to prevent MRSA is to practice good personal hygiene and avoid sharing clothes and towels.
Lichen Simplex Chronicus
Clinical presentation: Plaques, lichenification
Principal age group(s): People between 30 and 50 years old
Cause: Unknown
Course: Long-term, remits with treatment
Lichen simplex chronicus is a chronic skin condition caused by itching and scratching. Depression, anxiety, obsessive-compulsive disorder, and sleep disturbances may accompany and exacerbate the condition.
People with allergies and atopy (the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma, and atopic dermatitis) are predisposed to developing lichen simplex chronicus.
Continuous itching can eventually lead to thickened areas of skin. Antihistamines and steroids can be used to reduce the itch of lichen simplex chronicus. Once the itch is controlled, lichen simplex chronicus can remit (be relieved).
Pityriasis Rosea
Clinical presentation: Herald patch, papules, and scales (i.e., papulosquamous)
Principal age group(s): Any age, but most commonly seen in people between 10 and 35 years old
Cause: Unknown
Course: Rash can persist between three and five months
The herald patch is the hallmark of pityriasis rosea and appears on the trunk. The herald patch is a solitary, oval, flesh- or salmon-colored lesion with scaling at the border. It can be three centimeters (one inch) or more in diameter. One or two weeks after the appearance of the herald patch on the trunk, numerous smaller papulosquamous lesions fan out along ribs in a Christmas tree pattern.
Except for skin manifestations, there are no other symptoms of pityriasis rosea. In about half of cases, this condition is itchy. Pityriasis rosea resolves on its own and doesn’t require treatment. However, steroids and antihistamines may help reduce itching.
Psoriasis
Clinical presentation: Papules or plaques with silvery scales (i.e., papulosquamous)
Principal age group(s): Mostly adults, but can occur at any age
Cause: Autoimmune
Course: Long term
Psoriasis is a chronic, autoimmune, inflammatory skin disease that causes raised, red lesions with silvery scales. Plaque psoriasis is the most common type of psoriasis, accounting for about 80% to 90% of all cases of the disease. The plaques tend to enlarge slowly over time and present symmetrically on the elbows, knees, scalp, buttocks, and so forth.
Psoriasis can also affect the joints, resulting in psoriatic arthritis. New research points to the fact that psoriasis is a generalized inflammatory disorder that could raise cardiovascular risk, including stroke, heart attack, and death.
Mild psoriasis can be treated with hydrocortisone or other topical creams. Moderate to severe psoriasis can be treated with immunomodulators.
Rocky Mountain Spotted Fever
Clinical Presentation: Petechiae on the palms or soles
Principal age group(s): Any age
Cause: Tick-borne bacteria called Rickettsia rickettsii
Course: Weeks
While a rash is the classic sign of Rocky Mountain spotted fever, it is usually preceded by fever that occurs after a recent tick bite. Other symptoms include headache, chills, malaise, and body aches. The rash is more likely to appear in children and teens under 15 years of age.
The rash is first maculopapular (combining the features of macules and papules) and occurs on the wrists and ankles. The rash then spreads to the body, where it manifests as petechiae. Thrombocytopenia, or low platelet count, is common with Rocky Mountain spotted fever and causes petechiae.
Although Rocky Mountain spotted fever is found throughout the United States, it is most common in the southern Atlantic and south central states. Typically, people are infected with Rocky Mountain spotted fever during warm months of the year when ticks are active.
Several steps can be taken to prevent tick bites, including the following:
Wearing long-sleeved clothing
Using clothing and gear that is treated with permethrin
Performing tick checks on yourself and your pets
Showering as soon as you return home from a wooded area
The antibiotic doxycycline is used to treat this infection. Treatment with doxycycline is most effective when started within the first three to five days of the illness. Patients with neurological symptoms, vomiting, unstable vital signs, or compromised kidney function should be hospitalized.
Rosacea
Clinical presentation: Redness of the central face, with papules and pustules
Principal age group(s): Middle-aged adults, especially light-skinned people
Cause: Unknown
Course: Long term, flare-ups and remissions
Rosacea is a chronic disease that results in redness and bumps on the face and acne. It is an inflammatory condition that affects the face and the eyes; it typically progresses over time. Rosacea can cause facial discomfort.
Rosacea generally leads to the following:
Swollen nose
Thick facial skin
Flushing
Red lines on the face
Visible blood vessels on the face
Red, itchy eyes
Rosacea is most common among white women. Depending on type and severity, rosacea can be treated with antibiotics, lasers, or surgery.
Seborrhea
Clinical presentation: Poorly demarcated, red plaques with greasy, yellow scales usually around the scalp, eyebrows, forehead, cheeks, and nose; can also affect the body
Principal age group(s): Infants, adults, more common in men
Cause: Unknown
Course: Long term, relapsing
Seborrhea (also called seborrheic dermatitis) is a chronic, inflammatory condition that affects the parts of the body that have a lot of sebaceous glands, which produce an oily secretion called sebum. These areas include the face, scalp, torso, and groin.
Infants can have seborrhea of the scalp (cradle cap) or seborrhea that affects the diaper area. People with seborrhea may be more likely colonized with Malassezia, a type of yeast. Although people with HIV/AIDS often have seborrhea, the vast majority of people with seborrhea have normal immune systems. Seborrhea is mainly treated with topical antifungal medications.
Tinea
Clinical presentation: Red, ring-shaped skin patches with scaly borders; the central clearing may not be red
Principal age group(s): All ages
Cause: Fungus
Course: Usually resolves after over-the-counter antifungal treatment
Tinea refers to a group of diseases that are all caused by fungi called dermatophytes. Tinea can be spread by direct contact with an infected person, as well as contact with things an infected person has touched, such as towels or locker room floors. This fungus can affect different parts of the body and cause symptoms specific to those regions, including:
Ringworm (tinea corporis), wherein the rash takes the form of a ring on various parts of the body
Scalp ringworm (tinea capitis)
Athlete’s foot (tinea pedis)
Jock itch (tinea cruris)
Over-the-counter ointments and creams will usually treat tinea in the short term. More serious cases may require treatment with prescription medications.
Urticaria (Hives)
Clinical presentation: Wheals
Principal age group(s): All ages
Cause: Allergies to food or drugs, sometimes triggered by infections
Course: Typically resolves after a few days or weeks
Urticaria, or hives, and angioedema typically occur together. Angioedema refers to the swelling of the skin. Urticaria is treated with steroids and antihistamines, as well as the removal of any drugs or foods that are causing it.
Varicella (Chickenpox)
Clinical presentation: Papules, vesicles, pustules, and crusting
Principal age group(s): Children
Cause: Varicella zoster virus
Course: Transient, lasts two weeks
Initial infection with the varicella-zoster virus typically occurs in children and results in chickenpox. In adults, the first-time infection with the virus is often more severe and accompanied by pneumonia.
The hallmark of diagnosis with the varicella virus is a vesicular rash, which begins as papules and then changes into vesicles and pustules before finally crusting. The rash first involves the face, trunk, and scalp. Eventually, it moves toward the arms and legs. Other symptoms of chickenpox include headache, weakness, and loss of appetite.
Treatment of chickenpox is symptomatic, with acetaminophen given for fever, fluids given for hydration, and antihistamines, calamine lotion, and colloidal oatmeal baths applied to the skin. Antiviral therapy with acyclovir can reduce the duration of the fever and the severity of the symptoms. Childhood vaccination against chickenpox is recommended by the Centers for Disease Control and Prevention (CDC).
Venous Stasis Dermatitis
Clinical presentation: Discoloration, dryness, scaling, and itching, often in the legs
Principal age group(s): More common in older adults
Cause: Increased pressure in the veins caused by poor circulation
Course: Chronic
This type of eczema affects people who have poor circulation. It usually appears on the legs, where blood flow tends to be poorest. People with this condition have dry, itchy skin that can scale and flake. They can also develop skin ulcers.
Treatment for venous stasis dermatitis usually involves lifestyle modifications such as exercise and keeping the legs elevated. Compression stockings and topical medication can also help.
Summary
There are many different types of skin rashes. They can have very different appearances, depending on what’s causing them. For example, some may have a scaly or leathery appearance, while others may consist of red spots that are flat or elevated.
Rashes may be short-term or long-term. Treatment varies depending on the cause but may include topical therapies or oral medications.
Read the original article on Verywell Health.
