Dermatologists can treat more than 3,000 conditions. Below are some examples of those that they see most commonly: Acne: Among the most prevalent skin issues, acne has a range of causes that can lead to different types of pimples. Some people experience scarring, low self-esteem, and other complications. Dermatitis and eczema: Dermatitis is inflammation of the skin, and it typically leads to swelling with an itchy rash. There are various forms, including atopic dermatitis, which is the most common type of eczema. Fungal infections: These are common and sometimes involve the skin, nails, and hair. A group of yeasts called Candida can cause a wide range of fungal infections, including oral thrush, ringworm, athlete’s foot, and balanitis. Hair loss: About 80 million people in the U.S. have hereditary hair loss. A range of health issues can also cause hair loss, including head lice, which affects around 6–12 million children aged 3–11 years in the U.S. annually. Warts: These are contagious, benign skin growths that appear when a virus has infected the top layer of skin. A dermatologist can use a variety of treatments to remove persistent warts. Nail problems: Dermatologists also treat health issues that damage the skin around and under the nails. Ingrown nails, fungal infections, and various other conditions can cause this damage. Vitiligo: This involves the skin losing melanin, a pigment. As a result, some patches of skin are lighter in color than others. Psoriasis: This chronic autoimmune disorder speeds up the growth of skin cells, resulting in patches of skin that may be thick, red, purple, or silvery and scaly. There are several types of psoriasis. Rosacea: This causes redness in the face, sometimes with pus-filled bumps, visible blood vessels, and swelling of the eyelids. Symptoms can spread from the nose and cheeks to the forehead, chin, ears, chest, and back. Shingles, or herpes zoster: This viral infection causes a rash that may be painful. It may clear in a few weeks without treatment, but medical intervention can help speed recovery and prevent complications, which can be severe. Skin cancer: About 1 in 5 people in the U.S. develop a type of skin cancer by age 70. The most common forms are basal cell carcinoma, melanoma, and squamous cell carcinoma.