A rash can also be called dermatitis, which is any swelling (puffiness) or irritation of the skin. It can be red, dry, scaly, and itchy. Rashes also can include lumps, bumps, blisters, and even pimples. Most people have had a rash or two. Rashes are a very broad topic, but this Advisory has a narrow focus: dry skin and eczematous rashes. Dry skin is a problem faced by
almost all of us on occasion, but it’s always a problem if you have eczema.
The popular term for a group of spots or red, inflamed skin that is usually a symptom of an underlying condition or disorder. Often temporary, a rash is only rarely a sign of a serious problem. A rash may occur on only one area of the skin, or it could cover almost all of the body. Also, a rash may or may not be itchy. Some rashes, especially combined with a fever, can be signs of serious illnesses. Hives, also called urticaria, also can be serious because they can be a sign of an allergic reaction and the person may need immediate medical attention. Hives, which are reddish or pale swellings, appear on a person's body when a chemical called histamine is released in response to an allergen. The trigger could be a certain food, medicine, or insect bite. A virus also can cause hives.
Here are some other common types of rashes: Eczema, also called atopic dermatitis, is a common rash for kids. Eczema can cause dry, chapped, bumpy areas around the elbows and knees or more serious cases of red, scaly, and swollen skin all over the body. Irritant contact dermatitis is caused by contact with something irritating, such as a chemical, soap, or detergent. It can be red, swollen, and itchy. Even sunburn can be a kind of irritant dermatitis because it's red and may itch while it's healing. Allergic contact dermatitis is a rash caused by contact with an allergen. An allergen is something you are allergic to, such as rubber, hair dye, or nickel, a metal found in some jewelry. If you have nickel allergy, you might get a red, scaly, crusty rash wherever the jewelry touched the skin, like around your finger if you were wearing a ring. Urushiol, an oil or resin contained in poison ivy, oak, and sumac, also can cause this kind of rash.
There are many theories as to the development of skin rashes, but experts are not completely clear what causes some of them. Generally a skin rash is an intermittent symptom, fading and reappearing. Rashes may accompany a range of disorders and conditions, such as:
Infectious illness. A rash is symptom of many different kinds of childhood infectious illnesses, including chickenpox and scarlet fever. It may be triggered by other infections, such as Rocky Mountain spotted fever or ringworm.
Allergic reactions. One of the most common symptoms of an allergic reaction is an itchy rash. Contact dermatitis is a rash that appears after the skin is exposed to an allergen, such as metal, rubber, some cosmetics or lotions, or some types of plants (e.g. poison ivy). Drug reactions are another common allergic cause of rash; in this case, a rash is only one of a variety of possible symptoms, including fever, seizures, nausea and vomiting, diarrhea, heartbeat irregularities, and breathing problems. This rash usually appears soon after the first dose of the course of medicine is taken.
Autoimmune disorders. Conditions in which the immune system turns on the body itself, such as systemic lupus erythematosus or purpura, often have a characteristic rash.
Nutritional disorders. For example, scurvy, a disease caused by a lack of Vitamin C, has a rash as one of its symptoms.
Cancer. A few types of cancer, such as chronic lymphocytic leukemia, can be the underlying cause of a rash.
Rashes are very common conditions and can have many causes. Most rashes are not dangerous but rather are merely nuisance illnesses. Life-threatening skin rashes are rare, but when they do occur, you must identify them and go to a doctor quickly. Five potentially life-threatening disorders that have skin rash as the primary symptom are pemphigus vulgaris (PV), Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), toxic shock syndrome (TSS), and staphylococcal scalded skin syndrome (SSS).
Many babies will have a rash of some type during the first year of life. Rashes often appear as red, raised bumps on the skin. Sometimes a rash makes the skin look red or irritated, but without any raised areas. Most of the time, rashes go away by themselves. Here are two types of rashes that you can do something about. Cradle cap appears on the baby's head. The skin may be red and irritated. There may also be an oily, yellow crust on the scalp. It is common in babies whose parents avoid washing the baby's hair and scalp, especially over the "soft spot." Frequent shampooing will cure mild cases of cradle cap. Use a soft brush or washcloth to loosen the scaly crust. Rashes are extremely common in infancy, and are usually not serious at all and can be treated at home. Diaper rash is caused by prolonged skin contact with bacteria and the baby's waste products in a damp diaper. This rash has red, spotty sores and there may be an ammonia smell. In most cases the rash will respond within three days to drying efforts. A diaper rash that does not improve in this time may be a yeast infection requiring prescription medication. A doctor should be consulted if the rash is solid, bright red, causes fever, or the skin develops blisters, boils, or pus.
Infants also can get a rash on cheeks and chin caused by contact with food and stomach contents. This rash will come and go, but usually responds to a good cleaning after meals. About a third of all infants develop “acne” usually after the third week of life in response to their mothers' hormones before birth. This rash will disappear between weeks and a few months. Heat rash is a mass of tiny pink bumps on the back of the neck and upper back caused by blocked sweat glands. The rash usually appears during hot, humid weather, although a baby with a fever can also develop the rash.
A physician can make a diagnosis based on the medical history and the appearance of the rash, where it appears, and any other accompanying symptoms. Treatment of rashes focuses on resolving the underlying disorder and providing relief of the itching that often accompanies them. Soothing lotions or oral antihistamines can provide some relief, and topical antibiotics may be administered if the patient, particularly a child, has caused a secondary infection by scratching. The rash triggered by allergies should disappear as soon as the allergen is removed; drug rashes will fade when the patient stops taking the drug causing the allergy. For the treatment of diaper rash, the infant's skin should be exposed to the air as much as possible; ointments are not needed unless the skin is dry and cracked. Experts also recommend switching to cloth diapers and cleaning affected skin with plain water.
Some rashes can be prevented, depending on the triggering factor. A person known to be allergic to certain drugs or substances should avoid those things in order to prevent a rash. Diaper rash can be prevented by using cloth diapers and keeping the diaper area very clean, breast feeding, and changing diapers often.