Common Skin Conditions and Disease

What They Look Like and How They Are Treated

Many common skin conditions can be hard to tell apart. They can be caused by many different things (including infection, allergies, autoimmune disease, or cancer) and manifest with different symptoms.

While certain symptoms can narrow the possible causes—such as rash, swelling, discoloration, crusting, scaling, sores, and blister—you may need to see a skin specialist called a dermatologist to diagnose the cause and get the correct treatment.

This article looks at 12 skin conditions and the different forms they can take. It also offers an overview of treatment and describes some of the key risk factors and causes.

1

Acne

Close-up of acne on face
Acne vulgaris.

Jena Ardell / Getty Images

Acne is the most common skin condition in the United States, affecting up to 80% of people in their teens and 20s. It occurs when hair follicles get clogged by skin oil and dead skin debris.

There are several different types of acne:

  • Acne vulgaris: This is the most common type of acne.
  • Comedones: These non-inflammatory bumps are known as blackheads (open comedones) and whiteheads (closed comedones).
  • Nodular acne: There are large, solid lesions (nodules) that are painful and lodged deep within the skin.
  • Cystic acne: This is a severe form of acne that causes deep, painful, pus-filled lesions. It is also known as severe nodular or nodulocystic acne.

Treatment options for acne include over-the-counter products like benzoyl peroxide and salicylic acid and prescription medications like topical antibiotics and retinoids.

2

Eczema

Eczema rash
PansLaos / Getty Images.

Eczema (atopic dermatitis) is an inflammatory skin condition causing itchy, red, and swollen skin. Its cause is not known, but it is thought to involve an abnormal immune reaction.

Symptoms of eczema include:

  • Scaly and cracking patches of skin
  • Tiny bumps (papules)
  • Swelling
  • Oozing of clear fluid
  • Scratch marks and scarring
  • Thickening of the skin (lichenification)

While eczema is not an allergy, it is atopic (meaning related to allergies) and closely associated with conditions like hay fever and asthma. Genetics is believed to play a part.

Eczema treatment usually involves a combination of good skin care, moisturizing, topical steroids or calcineurin inhibitors, and oral immunosuppressants.

How Common Is Eczema?

Up to 15% of people experience some degree of atopic dermatitis in childhood, usually before age 5. Around 16.5 million adults and children in the United States are affected.

3

Bacterial Skin Infections

This photo contains content that some people may find graphic or disturbing.

A MRSA skin infection
MRSA. Wikimedia Commons

Bacterial skin infections are common and can vary in their severity from mild to ​life-threatening. Most are caused by one of two bacteria: Staphylococcus aureus or a form of Streptococcus. Symptoms can vary but often include redness, swelling, pain, or pus.

These and other bacteria can cause a wide range of infections:

  • Impetigo is a very contagious bacterial infection that occurs most often in young children.
  • Bacterial folliculitis is an infection of hair follicles. A form called hot tub folliculitis is most often caused by the bacteria Pseudomonas aeruginosa.
  • Furuncles or carbuncles are types of abscesses and boils that occur when an infection of a skin pore moves deeper into the skin.
  • Cellulitis is when a local skin infection moves into deep layers of tissue.
  • Erysipelas, also called "St. Anthony's fire," is an infection of the superficial layer of the skin which can be very painful.
  • MRSA: The condition, otherwise known as methicillin-resistant Staphylococcus aureus, is an infection commonly spread in hospitals that is resistant to many antibiotics.

Bacterial skin infections are typically treated with oral or intravenous antibiotics depending in on their severity.

4

Fungal Skin Infections

Ringworm. CDC/Dr. Lucille K. Georg

Many fungal skin infections are transmitted, meaning passed through direct contact or contact with contaminated items. Others are opportunistic, meaning that fungus naturally inhabiting the skin will suddenly overgrow when the immune system is down.

Symptoms can vary but often involve a ring-like rash with raised edges. There may also be peeling, cracking, itching, and tiny blisters.

Fungal skin infections include:

Fungal skin infections are treated with antifungals. Milder infections may be treated with an over-the-counter antifungal like Lotrimin (terbinafine), while more serious infections may need oral antifungals.

5

Contact Dermatitis

Contact dermatitis on the skin
Irritant contact dermatitis.

Reproduced with permission from ©DermNet NZ and ©Waikato District Health Board

Contact dermatitis is a skin reaction that occurs when an irritant or allergen (allergy-causing substance) comes into contact with the skin. This can lead to symptoms like:

  • Reddened rash or bumps
  • Blisters or hives 
  • Itchy, burning skin
  • Thickening of skin

With allergic contact dermatitis (ACD), the immune system will respond by releasing an antibody called immunoglobulin E (IgE), which triggers the release of chemicals like histamine that cause a local skin reaction. Common triggers include nickel, chromium, dyes, poison ivy, and poison oak.

With irritant contact dermatitis (ICD), the immune system will also respond, but IgE won't be involved. Instead, the immune reaction will be more generalized. Common triggers include solvents, latex, cosmetics, strong soaps, detergents, and household cleaners.

Reactions from ACD often occur 24 to 72 hours after contact, causing itchy skin and occasionally blisters that can persist for a week or more. With IDC, the reaction tends to be immediate with pain rather than itch as well as dry, cracking skin.

Contact dermatitis may benefit from oral antihistamines to reduce itchiness and swelling. Topical steroids like hydrocortisone cream can also help.

6

Herpes

cold sore
Cold sore on lip. Todd Keith/E+/Getty Images

Herpes simplex virus (HSV) is a highly contagious virus that causes cold sores and genital herpes. Once you are infected, the virus stays in your body forever and can reactivate at any time.

There are two types:

Both HSV-1 and HSV-2 can start with a prickly or burning sensation prior to the outbreak of tiny blisters. These blisters can then grow and converge, causing a painful, open sore as the blisters rupture. After crusting, the sore will gradually heal, and the virus will go into remission.

If started within 48 hours of the first sign of symptoms, antiviral drugs like Zovirax (acyclovir) or Valtrex (valacyclovir) may reduce the duration and severity of the infection.

7

Chickenpox and Shingles

This photo contains content that some people may find graphic or disturbing.

Herpesviridae Chickenpox
Chickenpox blisters. Smith Collection/Gado / Getty Images

Varicella-zoster virus (VZV) is a type of herpes virus that causes chickenpox. The virus is highly contagious and can be passed from person to person by directly touching the chickenpox blisters or saliva or mucus of an infected person.

Chickenpox often starts with a fever, headache, sore throat, or stomach ache before a red, itchy rash appears on the belly, back, or face. The rash will form into tiny blisters that fill with pus, rupture, and crust over.

As with HSV, VZV will stay inside the body forever and can suddenly reactivate in later life, causing shingles.

With a shingles outbreak, the blistering rash will appear on a specific part of one side of the body serviced by a spinal nerve (called a dermatome). The outbreak is painful and can cause scarring and chronic nerve pain even after the blisters heal.

As with herpes, immediate antiviral treatment can reduce the duration and severity of the infection. Both chickenpox and shingles can also be prevented with vaccines.

8

Psoriasis

This photo contains content that some people may find graphic or disturbing.

A psoriasis plaque
Classic plaque psoriasis.

Lipowski / Getty Images

Many autoimmune diseases can cause a skin rash or lesions, including lupus, Sjögren's syndrome, and celiac disease. They do so when the immune system targets and attacks different skin cells with inflammation.

The autoimmune disease characterized by skin lesions is psoriasis. This condition affects 3% of adults over age 20, or roughly 7.5 million people in the United States.

The disease targets skin cells known as keratinocytes with inflammation, causing them to multiply faster than they can be shed. This leads to patches of scaly, inflamed skin called plaques. The scalp, elbows, and knees are most commonly affected, but other parts of the body can be affected as well.

In addition to classic plaque psoriasis, there are other forms known as:

  • Guttate psoriasis: This usually affects children who have an upper respiratory infection, causing small, teardrop-shaped dots on the torso or limbs.
  • Pustular psoriasis: This causes pus-filled bumps surrounded by red skin. It usually affects the hands and feet.
  • Inverse psoriasis: This appears as smooth, red patches in folds of skin, such as beneath the breasts or in the groin or armpits.

The treatment may involve steroid creams, oral or topical retinoids, oral or injected methotrexate, phototherapy, biologic drugs, and immunosuppressants.

9

Hives and Angioedema

A close up of Caucasian skin with hives
Hives (urticaria).

Wikicommons

Urticaria (hives) and angioedema are two skin reactions that cause a rash as fluids accumulate below the upper layer of skin known as the epidermis.

Hives and angioedema are the result of an inflammatory reaction that causes capillaries to leak fluid into surrounding tissues. The outbreak can be triggered by different things, including an allergy, autoimmune disease, infection, stress, medications, or temperature change.

While related, the two conditions vary in different ways:

  • With urticaria, the leakage of fluid occurs in the underlying skin layer called the dermis. This causes red, raised, itchy hives, usually with well-defined borders. They can appear on any surface of the skin.
  • With angioedema, the leakage is in subcutaneous tissues underlying the dermis. The swelling is more generalized, affecting the face and sometimes the hands. The swelling can be painful or itchy.

Depending on the cause, urticaria may be treated with antihistamines, oral steroids, immunosuppressants, or leukotriene modifiers like Singulair (montelukast).

10

Rosecea

This photo contains content that some people may find graphic or disturbing.

Rosacea. Erythema and telangiectasia are seen over the cheeks, nasolabial area and nose. Inflammatory papules and pustules can be observed over the nose. The absence of comedos is a helpful tool to distinguish rosacea from acne.
Rosacea.

Wikimedia Commons/CC-BY-2.0

Rosacea is a chronic inflammatory skin condition characterized by redness and/or bumps on the face. The cause is unknown but is thought to be due to a combination of genetic and environmental factors.

Symptoms of rosacea include:

  • Redness and flushing of the cheeks, forehead, and nose 
  • Tiny bumps or pustules (pus-filled bumps), usually in clusters 
  • Spider veins (telangiectasia}
  • Thickened, bumpy skin on the nose

Symptoms can worsen or improve, triggered by things like excess sun exposure, alcohol, spicy food, cigarette smoke, and hot or cold temperatures.

The treatment of rosacea involves the avoidance of triggers, gentle skin care, sunscreen, and possibly antibiotics and anti-inflammatory drugs. Laser treatments can reduce some of the cosmetic effects of rosacea.

11

Vitaligo

vitiligo and thyroid disease
Vitiligo. Axel Bueckert / EyeEm / Getty Images

Vitiligo is a chronic autoimmune disorder that causes patches of skin to lose pigment. The cause is unknown, but it is thought to be related to genetic factors and influenced by stress and sun exposure.

Vitiligo most commonly affects the extremities (especially the hands and wrists) and face (particularly around the mouth, eyes, and nostrils). The genitals and skin around the belly button are also commonly affected.

The loss of color occurs in smooth patches that initially start small but often grow and change shape. Some people experience itching before a new patch appears.

The treatment involves topical steroids and calcineurin inhibitors that suppress the immune response. Phototherapy (light therapy) is also commonly used.

In 2022, a new topical drug called Opzelura (ruxolitinib) was licensed for the treatment of vitiligo in people 12 years of age and older.

12

Skin Cancer

This photo contains content that some people may find graphic or disturbing.

Squamous Cell Carcinoma (Central Hyperkeratosis
Squamous Cell Carcinoma.

https://dermnetnz.org/topics/squamous-cell-carcinoma-on-the-face-images/?stage=Live

A less likely cause of a skin lesion is skin cancer. These cancers are largely the consequence of excessive sun exposure, causing skin cells to mutate and grow out of control. Other factors may contribute, including genetics and skin tone.

Some of the more common skin cancers are:

  • Basal cell carcinoma (BCC): This is the most common type affecting cells in the middle part of the epidermis called basal cells. This slow-growing cancer may look like a reddish patch, shiny bump, or sore that never heals. It is often seen on sun-exposed areas like the head and neck.
  • Squamous cell carcinoma (SCC): This second most common type affects squamous cells on the outermost layer of the epidermis. It often affects the neck, ears, eyelids, and face, as well as the arms and legs. SCC may appear as reddish or brownish patches with rough, scaly, or crusted surfaces.
  • Melanoma is a less common but potentially deadly cancer that affects cells called melanocytes in the lowest part of the epidermis. It can quickly spread (metastasize) if not treated early. Melanoma can take many forms and look like a sore, age spot, bruise, or cyst with an uneven shape, color, and texture.

Skin cancer is often treated with surgery to remove the tumor and a surrounding margin of normal skin. Sometimes chemotherapy or radiation may be used depending on the stage of the cancer (particularly with SCC and melanoma).

How Common Is Skin Cancer?

Around 5.4 million basal and squamous cell skin cancers are diagnosed each year in the United States, according to the American Cancer Society. Melanoma accounts for nearly 100,000 cases each year.

Summary

Some of the most common skin conditions and diseases are acne, eczema, bacterial skin infections, fungal skin infections, contact dermatitis, herpes, chickenpox and shingles, psoriasis, hive, angioedema, rosacea, and vitiligo. Skin cancer is a less likely cause but still affects around 5.5 million people in the United States each year.

28 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • Kasper, Dennis L., Anthony S. Fauci, Stephen L. Hauser, Dan L. Longo, J. Larry Jameson, and Joseph Loscalzo. Harrison's Principles of Internal Medicine. New York: McGraw Hill Education, 2015. Print.

By Heather L. Brannon, MD
Heather L. Brannon, MD, is a family practice physician in Mauldin, South Carolina. She has been in practice for over 20 years.