Dermatology is an area of medicine concerned with the health of the skin and diseases of the hair, nails, and mucous membranes. The skin is the largest organ in the body. It is the first line of defence against bacteria and injury, and often reflects overall health.

Common conditions

Vitiligo is just one of the over 3,000 diseases handled by dermatologists.

Dermatologists can treat over 3,000 different diseases.

The practice of dermatology requires a great depth of clinical knowledge. Dermatologists need to know the numerous internal conditions that can cause skin symptoms.

Here are some examples of the more common conditions dermatologists are trained to treat.

Vitiligo: The skin loses melanin, leading to patches of lighter colored skin.

Acne: One of the most common diseases in the U.S., acne is a disease affecting the oil glands of the skin. It has a range of causes that lead to many different kinds of pimples. Acne can result in depression, low self-esteem, and scarring.

Dermatitis and eczema: Dermatitis is inflammation of the skin. It typically leads to swelling with an itchy rash. Dermatitis takes different forms, including contact dermatitis, seborrheic dermatitis, and atopic dermatitis. Each affects the skin differently.

Fungal infections: Fungus can infect the skin, nails, and hair. Fungal infections are common, and symptoms are normally mild. They can cause more serious symptoms for people with reduced immunity. A group of yeasts called Candida can cause a wide range of infections, including oral thrush and balanitis.

Hair disorders: Hereditary hair loss is one kind most commonly seen. The loss of hair may be the result of an underlying condition, such as alopecia, or an isolated issue. Hair can also be affected by head lice.

Nail problems: Dermatologists also treat conditions affecting the nails. These complaints often consist of fungal infections and ingrowing toenails. Nail problems can be indicative of other underlying conditions.

Psoriasis: This is a chronic, autoimmune skin disorder that speeds up the growth of skin cells. This rapid growth results in thick, red skin and silvery scales. There are several different types of psoriasis. Psoriasis can sometimes have a similar appearance to eczema.

Rosacea: Rosacea causes redness in the face, similar to blushing. Small, pus-filled bumps often appear, and rosacea can also lead to visible blood vessels and swollen eyelids. Rosacea can spread from the nose and cheeks to the forehead, chin, ears, chest, and back. Women with fair skin who are in middle aged most often experience rosacea.

Skin cancer: Almost 5 million people receive treatment for skin cancer in the U.S. every year, and one in five people in the U.S. will develop a form of skin cancer in their lifetime. The most common forms of skin cancer are basal cell carcinoma (BCC), melanoma, and squamous cell carcinoma (SCC). Early treatment can resolve most skin cancers.

Shingles, or herpes zoster: This viral infection affects the nerve endings in the skin and causes a painful rash. Although the condition clears after a few weeks without treatment, intervention is recommended to speed up recovery and prevent long-lasting pain, numbness, and itching after the disease has gone. Shingles can also potentially damage the eyes.

Warts: These are contagious, benign skin growths that appear when a virus infects the top layer of skin. Warts may indicate an underlying issue with immunity, but they often resolve without treatment. A dermatologist can use a variety of treatments to remove persistent warts.

Procedures

Laser hair removal is one of many dermatological procedures.

Dermatologists use a range of medical and cosmetic surgical procedures.

Many dermatological conditions can be treated with medication and non-invasive therapy, but some require surgical intervention or more invasive treatment. Dermatological procedures can take place in an outpatient setting, such as a doctor's office, or during a hospitalization.

Biopsies: Skin biopsies are primarily carried out to diagnose or rule out certain skin conditions. There are three commonly-performed types of skin biopsy. Shave biopsies remove small sections of the top layer of skin, punch biopsies remove a small circular section including deeper layers, and excision biopsies remove entire areas of abnormal-looking skin.

Chemical peels: A chemical solution is applied to the skin. It causes a layer of skin to peel off, leaving a layer of regenerated skin underneath that is typically smoother. Dermatologists use this procedure to treat sun-damaged skin and some types of acne. It can also address complaints of a more cosmetic nature, such as age spots and lines under the eyes.

Cosmetic injections: Wrinkles, scarring, and lost facial fullness can be temporarily reduced with injections. A dermatologist can inject botulinum toxin therapy, or fillers such as collagen and fat, during an office visit. Results of this treatment tend to last for a few months, and injections need to be repeated periodically. Some people can develop antibodies to Botox that make repeat treatments ineffective.

Cryotherapy: This is a quick and common form of treatment for many benign skin conditions, such as warts. Skin lesions are frozen to destroy the affected skin cells, often using liquid nitrogen.

Dermabrasion: Using a high-speed rotating brush, a dermatologist removes the top layer of skin, surgically eroding scar tissue, fine wrinkles, tattoos, and potentially precancerous skin patches.

Excisions of lesions: Skin lesions are excised for several reasons. They are removed to prevent disease from spreading, for cosmetic reasons, to prevent repeat infection, to alleviate symptoms, and for diagnosis. Depending on the size of the lesion, local or general anesthetic can be used to numb the area before removal.

Hair removal and restoration: Hair loss can be treated with hair transplantation or surgery to the scalp. Unwanted body hair can be removed with laser hair epilation, or electrolysis that destroys hair follicles.

Laser surgery: Dermatologists can use a special light beam to treat a variety of skin complaints. These include tumors, warts, moles, tattoos, birthmarks, scars, wrinkles, and unwanted hair.

Mohs surgery: This is a specific type of surgery for skin cancer. Layers of skin are removed and examined under a microscope to get rid of cancerous cells. Successive layers are removed until the surgeon can find no more cancer cells. Mohs surgery is only performed by Mohs surgeons and requires additional medical training.

Psoralen combined with ultraviolet A (PUVA): Psoralen is a drug that makes the skin more sensitive to radiation treatment. PUVA is used to treat severe skin diseases, such as psoriasis, dermatitis, and vitiligo.

Skin grafts and flaps: Dermatologists can repair missing skin using skin from elsewhere on the body. Skin can be grafted from a free piece of tissue without its own blood supply, or a skin flap can be created from skin tissue near the area of skin loss.

Tumescent liposuction: Dermatologists use a process called tumescent liposuction to remove excess fat from the body. Large volumes of local anesthetic are injected into the fatty tissue, which is then sucked from the body. Tumescent liposuction is not a treatment for obesity but a cosmetic procedure for body contouring. Dermatologists can also use lasers to selectively burst fat cells and help remove tumescent fluid.

Vein therapy: Superficial leg veins are small, dilated surface veins. They are also known as spider veins and are often removed for cosmetic reasons. Sclerotherapy is usually the preferred treatment for spider veins. Dermatologists insert either foam or a solution into the vein. This irritates the lining, causing it to shut. The vein then becomes less distinct or disappears completely.