Restless Legs Syndrome, also called RLS or Willis-Ekbom Disease, is a neurologic and sensory disorder. It causes uncomfortable sensations in the legs that are only relieved by walking or by moving the legs.

The cause is not in the legs but in the brain. One theory is low levels of iron in the brain.

RLS may be hereditary. It is more common in women than in men, especially in middle age. It may get more severe as the person gets older.

Symptoms may happen only a few times a week and are usually worse at night.

There will be an irresistible urge to move the legs in order to relieve the uncomfortable sensations; difficulty sleeping, with daytime exhaustion and inability to concentrate; and sometimes depression and anxiety due to the effect on quality of life.

Diagnosis is made through patient history and physical examination. Blood tests and sleep studies may be done.

Treatment involves first addressing any underlying medical condition, such as iron deficiency. In some cases, anti-seizure medications can be helpful.

Itchy skin is also called pruritis. There are a number of "normal" causes for itching, meaning the cause is not disease-related and does not result in seriously damaged skin.

The most common causes are:

Diagnosis is made through physical examination and sometimes allergy tests.

Treatment involves bathing only with mild, hypoallergenic soap; regular moisturizing with unscented lotion; wearing soft, loose, non-synthetic clothing; avoiding any substances that seem to provoke the itching; and sometimes prescription medicated creams.

Rarity: Common

Top Symptoms: feeling itchy or tingling all over

Symptoms that always occur with normal episode of itchy skin: feeling itchy or tingling all over

Urgency: Self-treatment

Insect bites are very common. They often cause itchiness, redness, and some swelling. Most insect bites can be treated at home.

Rarity: Common

Top Symptoms:

Urgency: Self-treatment

Atopic dermatitis, also called eczema, dermatitis, atopic eczema, or AD, is a chronic skin condition with an itchy rash.

AD is not contagious. It is caused by a genetic condition that affects the skin's ability to protect itself from bacteria and allergens.

AD is most often seen in infants and young children. Most susceptible are those with a family history of AD, asthma, or hay fever.

Infants will have a dry, scaly, itchy rash on the scalp, forehead, and cheeks. Older children will have the rash in the creases of elbows, knees, and buttocks.

Without treatment, a child may have trouble sleeping due to the intense itching. Constant scratching may cause skin infections and the skin may turn thickened and leathery.

Diagnosis is made through physical examination, patient history, and allergen skin tests.

AD cannot be cured, but can be controlled through prescribed medications, skin care, stress management, and treatment of food allergies. Those with AD often have allergies to milk, nuts, and shellfish. Keeping the skin clean and moisturized helps prevent flareups.

A dermatofibroma is a fairly common skin growth that usually appears on the lower legs, but may appear anywhere on the body. These mole-like growths are benign (noncancerous.)

The cause is not known, though a dermatofibroma may appear after a minor injury. The growths are not contagious.

Dermatofibromas are most common in adults and are rarely found in children.

Symptoms include a hard, raised growth that is red, pink, or brown and less than half an inch across. They are usually painless but may be tender or itchy, and may appear alone or in groups.

Any new growth on the skin should be seen by a medical provider, especially if the growth is very dark in color or changes its shape or appearance quickly.

Diagnosis is made through physical examination and sometimes biopsy.

A dermatofibroma does not require treatment unless it is interfering with clothing or is unsightly. They can be surgically removed, though this will leave a scar and the growth may eventually return.

Allergic contact dermatitis means the skin has touched something that provoked an allergic reaction, causing inflammation and irritation.

"Contact" means the allergic reaction came from touching something, not from consuming something. The first exposure to the substance sensitizes the immune system, and then the second exposure actually causes the symptoms.

The most common causes of allergic contact dermatitis are:

Symptoms include red, itching, scaling, flaking skin that may be painful due to the irritation and inflammation.

Diagnosis is made through first avoiding contact with any suspected substance, to see if the dermatitis clears. Patch testing can be done if the results are not certain.

Treatment involves fully avoiding the allergy-provoking substance and using topical steroid cream as prescribed. Cool compresses and calamine lotion can help to ease the discomfort.

Rarity: Common

Top Symptoms: lower leg redness, lower leg itch, scabbed area of the lower leg

Symptoms that always occur with allergic contact dermatitis of the lower leg: lower leg redness

Urgency: Self-treatment