Acne vulgaris is a disorder of the pilosebaceous follicles found in the face and upper trunk. At puberty androgens increase the production of sebum from enlarged sebaceous glands that become blocked. Comedones (follicles impacted and distended by incompletely desquamated keratinocytes and sebum) may be open (blackheads) or closed (whiteheads). Inflammation leads to papules, pustules and nodules. Acne can cause severe psychological problems, undermining self-assurance and self-esteem at a vulnerable time in life. Read more on: patient.info
Actinic keratosis (AK), also known as a solar keratosis, is a crusty, scaly growth caused by damage from exposure to ultraviolet (UV) radiation. Read more on: skincancer.org
Atypical moles are unusual-looking benign (noncancerous) moles, also known as dysplastic nevi (the plural of “nevus,” or mole). Atypical moles may resemble melanoma, and people who have them are at increased risk of developing melanoma in a mole or elsewhere on the body. Read more on: skincancer.org
Cellulitis is a common and potentially serious infection caused by bacteria. The bacteria infect the deep layers of skin and tissue beneath the skin. The first sign of cellulitis is usually red and swollen skin. When you touch the infected area, it often feels warm and tender. Read more on: aad.org
Cradle cap is a type of seborrheic dermatitis that many infants get. Scaly, greasy patches can become thick and crusty. Cradle cap is harmless and goes away on its own within a few months. Read more on: http://aad.org
Almost everyone gets this type of eczema at least once. We get contact dermatitis when something that our skin touches causes a rash. Some rashes happen immediately. Most take time to appear. Read more on: aad.org
Excessive sweating (hyperhidrosis) is a common problem, especially of the palms, armpits and soles. It can be distressing and can have a serious impact on your life. In some cases, affected people avoid social contact with others because of embarrassment about the problem. However, the condition is usually treatable. Read more on: patient.info
Folliculitis means an inflammation or infection of the hair follicles of the skin. Read more on: patient.info
General warts are benign (not cancerous) skin growths that appear when a virus infects the top layer of the skin. Viruses that cause warts are called human papillomavirus (genital warts). Wart viruses are contagious. Warts can spread by contact with the wart or something that touched the wart. Read more on: aad.org
In most cases, granuloma annulare isn’t itchy or painful, so no treatment is necessary. The lesions usually disappear on their own within two years. If you’re bothered by how your skin looks, your doctor can prescribe medications that will speed the disappearance of the lesions. Read more on: http://www.mayoclinic.org
Grover’s disease (transient acantholytic dermatosis) is a benign condition that appears suddenly as itchy red spots on the trunk, most often in older men. Read more on: http://aad.org
Herpes simplex is a common viral infection. If you’ve ever had a cold sore or fever blister, you picked up the herpes simplex virus. Most cold sores are caused by herpes simplex virus type 1 (HSV-1). Read more on: aad.org
Hypertrichosis is excessive hair growth over and above the normal for the age, sex and race of an individual, in contrast to hirsutism, which is excess hair growth in women following a male distribution pattern. Hypertrichosis can develop all over the body or can be isolated to small patches. Hypertrichosis may be congenital (present at birth) or acquired (arises later in life). Read more on: dermnetnz.org
Impetigo is a common skin infection, especially in children. It’s also highly contagious. Most people get impetigo through skin-to-skin contact with someone who has it. Children and athletes like wrestlers and football players often get it this way. Read more on: aad.org
Keloid is an overgrowth of the scar tissue that develops around a wound, usually after the wound has healed. A keloid scar is sometimes confused with a hypertrophic scar. However, keloid usually grows beyond the borders of the original wound whereas in a hypertrophic scar the tissue stays within the wound border. Read more on: patient.info
Lichen planus is not contagious. You cannot get this disease from someone else, and you cannot give it to anyone. Lichen planus is not a type of cancer. Read more on: https://www.aad.org
Lipoma is a soft fatty lump. It is a non-cancerous (benign) growth made up from fat cells that clump together. A lipoma can occur in any part of the body where there are fat cells. Read more on: patient.info
Melasma is a common skin problem. It causes brown to gray-brown patches on the face. Most people get it on their cheeks, bridge of their nose, forehead, chin, and above their upper lip. It also can appear on other parts of the body that get lots of sun, such as the forearms and neck. One of the most common treatments for melasma is sun protection. Read more on: aad.org
Molluscum contagiosum is a common skin disease. It is caused by a virus. This virus easily spreads from person to person. People can get molluscum by sharing towels and clothing. Wrestlers and gymnasts may get it from touching infected mats. Often the only sign of molluscum is pink or flesh-colored bumps on the skin. Read more on: aad.org
Psoriasis is a chronic (long-lasting) disease. It develops when a person’s immune system sends faulty signals that tell skin cells to grow too quickly. New skin cells form in days rather than weeks. The body does not shed these excess skin cells. The skin cells pile up on the surface of the skin, causing patches of psoriasis to appear. Psoriasis may look contagious, but it’s not. Read more on: aad.org
Pyogenic granulomas are common benign vascular lesions of the skin and mucosa. They are not infective, purulent or granulomatous (as the name might suggest) – rather, a reactive inflammatory mass of blood vessels and a few fibroblasts within the dermis of the skin. Read more on: patient.info
If you have ringworm, you may think you have worms in your skin or a disease caused by worms. You have neither. Ringworm is actually a skin infection caused by fungus. No worms involved. The name “ringworm” probably comes from the rash that many people see. On the skin, the rash often has a ring-shaped pattern and a raised, scaly border that snakes its way around the edge like a worm. Read more on: aad.org
Rosacea is a skin condition that affects parts of your face. Symptoms can include facial flushing, facial redness, spots, thickening of your skin, and eye problems such as dry eyes and sore eyelids. Many cases are mild. Spots can usually be cleared with antibiotic treatment. Other treatments may be used for other symptoms. A complication that affects the front of the eye (the cornea) is uncommon but serious. Read more on: patient.info
A mite causes the common skin condition called scabies. Called the human itch mite, this eight-legged bug is so small that you cannot see it on the skin. People get scabies when the mite burrows into the top layer of skin to live and feed. When the skin reacts to the mite, an extremely itchy rash develops. Read more on: aad.org
When an adult gets seborrheic dermatitis, the condition can come and go for the rest of the person’s life. Flare-ups are common when the weather turns cold and dry. Stress also can trigger a flare-up. The good news is that treatment can reduce flare-ups and bring relief. Read more on: aad.org
Seborrheic keratosis is a common skin growth. It may look worrisome, but it is benign (not cancer). These growths often appear in middle-aged and older adults. Some people get just one. It is, however, more common to have many. They are not contagious. Read more on: aad.org
Anyone who has had chickenpox can get shingles. After the chickenpox clears, the virus stays in the body. If the virus reactivates (wakes up), the result is shingles — a painful, blistering rash. Read more on: aad.org
Skin tags are small, often pedunculated, skin-coloured or brown papules that occur most frequently where there are skin folds. Common sites are the neck, axillae, groin and eyelids. They are also known as acrochordons. They are usually 0.2 to 0.5 cm in diameter. Read more on: patient.info
Stasis dermatitis develops in people who have poor circulation. Because poor blood flow usually occurs in the lower legs, this is where stasis dermatitis often develops. It may occur in one or both legs. Read more on: aad.org
We all have yeast living on our skin. When the yeast grow out of control, a person can get a skin disease called tinea versicolor. Your dermatologist may tell you that you have a fungal infection on your skin. Yeast is a type of fungus. Many people get tinea versicolor. Read more on: aad.org
Vitiligo causes the skin to lose color. Patches of lighter skin appear. Some people develop a few patches. Others lose much more skin color. Patches of hair can turn white. Even an eye can lose some of its color. Read more on: aad.org