In-depth

Actinic keratosis

Actinic keratosis is a skin growth that appears as a rough, scaly patch. Left untreated, skin cancer sometimes develops.

Age spots (liver spots)

Age spots tell more than your age. They also indicate how much time you've spent in the sun.

Anhidrosis

Basal cell carcinoma

Most cases of basal cell carcinoma, the most common type of skin cancer, can usually be prevented. Learn how.

Bullous pemphigoid

Bullous pemphigoid, a rare skin condition that usually affects older adults, results in large blisters and severe itching.

Ehlers-Danlos syndrome

Ehlers-Danlos syndrome (EDS) includes a group of uncommon genetic disorders that mainly affect the joints, skin and walls of blood vessels.

Epidermolysis bullosa

Granuloma annulare

Granuloma annulare is a chronic skin condition that causes raised, reddish or skin-colored bumps (lesions) that form ring patterns, usually on the hands and feet.

Henoch-Schonlein purpura

Henoch-Schonlein purpura causes inflammation of small blood vessels (vasculitis) and often a purplish rash. It's most common in children ages 2 to 6.

Ichthyosis vulgaris

Ichthyosis vulgaris, also called fish scale disease, causes severely dry, scaly skin. With no cure available, treatments focus on controlling the symptoms.

Krabbe disease

Krabbe disease is a rare, inherited disorder — most often affecting infants — that impairs functioning of the central nervous system and usually leads to early death.

Lichen nitidus

Lichen nitidus, a rare condition in which tiny bumps emerge on the skin, usually clears up without treatment.

Lichen planus

Lichen planus is an inflammatory disorder that results in lesions on the skin or mucous membranes.

Lipoma

A lipoma is a fatty tumor located just below the skin. Treatment usually isn't necessary.

Melanoma

The risk of melanoma among young adults, especially women, is on the rise. Find out how to reduce your risk of this dangerous skin cancer.

Merkel cell carcinoma

Merkel cell carcinoma is a rare, aggressive skin cancer. Chronic sun exposure or a weak immune system may increase your risk of developing it.

Moles

Neurodermatitis

Neurodermatitis is a stubborn skin condition characterized by chronic itching and scratching. It's not serious — but stopping the scratching can be challenging.

Pemphigus

Pemphigus is a group of uncommon skin disorders that cause blisters of the skin or mucous membranes. Untreated, pemphigus may be fatal.

Pityriasis rosea

Pityriasis rosea is a common skin condition characterized by a fine, scaly rash that typically starts as one large spot and then spreads.

Polymorphous light eruption

Polymorphous light eruption is a sun-induced skin rash affecting people who develop a sensitivity to sunlight.

Psoriasis

Though psoriasis can be uncomfortable and sometimes painful, you can take steps to improve your symptoms.

Pyoderma gangrenosum

Pyoderma gangrenosum causes painful, widening ulcers to appear on your skin. Prompt treatment reduces the risk of scarring.

Sarcoidosis

Sarcoidosis starts in your lungs but can cause inflammation in any part of your body. It can last a lifetime, or disappear in a few years.

Seborrheic dermatitis

Stubborn, itchy dandruff can be a sign of seborrheic dermatitis. Find out what you can do to treat this flaky skin condition.

Seborrheic keratosis

Older adults often have at least one seborrheic keratosis. Find out if you need to be concerned about this common skin growth.

Skin cancer

The risk of melanoma, one form of skin cancer, is on the rise among young adults. Most skin cancers are preventable. Find out how to reduce your risk.

Stevens-Johnson syndrome

Stevens-Johnson syndrome is a disorder of the skin and mucous membranes. Often, this severe adverse reaction is caused by medication or an infection.

Sun allergy

Sun allergy can be a bothersome condition. Learn about causes and treatment.

Sweet's syndrome

Sweet's syndrome, also called acute febrile neutrophilic dermatosis, is a skin disorder marked by a rash, fever and high white blood cell count.

Vitiligo

Feb. 16, 2013