A rash is a noticeable change in the texture or color of the skin. The skin may become itchy, bumpy, chapped, scaly, or otherwise irritated. Rashes are caused by a wide range of conditions, including allergies, medication, cosmetics, and various diseases.
Contact dermatitis is a common cause of rashes. Contact rashes occur when you touch something that causes a reaction. Most contact rashes can be treated without the help of a doctor. A rash may be itchy, but scratching can make it worse and prevent it from healing.
Contact dermatitis can be caused by coming into contact with:
- beauty products, soaps, and laundry detergent
- dyes in clothing
- chemicals in rubber, elastic, or latex
- poisonous plants such as poison oak, poison ivy, or poison sumac Drug rashes are caused by medication.
They can form as:
- an allergic reaction
- a side effect
- a result of sensitivity to sunlight
Other types of rashes include:
- eczema: a common rash for people with asthma or allergies. The rash is often reddish and itchy, with a scaly texture.
- bug bites: tick bites are of particular concern, as they can transmit disease
- psoriasis: a scaly, itchy, red rash that forms along the scalp and joints
- dandruff: an itchy, flaky rash on the scalp. On an infant, dandruff is called cradle cap.
- seborrheic dermatitis: dandruff that occurs on the ears, mouth, nose, or somewhere besides the scalp
Children are particularly prone to rashes from illnesses such as:
- chicken pox: avirus that causes itchy blisters
- measles: a respiratory infection
- scarlet fever: a bacterial disease (streptococcus infection) that requires antibiotics
- hand, foot, and mouth disease: a virus that causes red lesions
- fifth disease: a red, flat rash on the face, upper arms, and legs
- Kawasaki disease:an autoimmune disease that affects the blood vessels
- impetigo: a bacterial infection that forms red, wet sores that crust over Medical diseases can cause rashes as well. These include lupus erythematosus (a long-term disorder of the autoimmune system) and rheumatoid arthritis (long-term inflammation of the joints).