Introduction

Rashes are a common skin condition that everyone experiences at one time or another.  There are numerous causes of rashes, ranging from allergic reactions, infections, and medical conditions to insect stings.  Some types of rashes can be treated at home with over-the-counter or home remedies.  A doctor should evaluate severe rashes or those that get worse instead of better.

Anatomy

Your skin covers your body and protects it from the environment.  The outermost layer of skin is called the epidermis.

Causes

Rashes can occur for many different reasons and there are different types of rashes.  Some common causes of rashes include:

• Allergens or irritants that directly contact the skin cause contact dermatitis.  Examples of allergens include poison ivy and latex.  Examples of irritants include toxic chemicals.
• Bacterial skin infections, such as Staph infections
• Eczema (atopic dermatitis) is a hereditary condition
• Fungal infections, such as athlete’s foot
• Impetigo is a bacterial infection that is common in children
• Insect stings
• Medical conditions, such as lupus
• Medication allergies
• Psoriasis is a hereditary condition
• Viral rashes are caused by viral infections, such as shingles and chicken pox

Symptoms

Symptoms of rashes differ depending on the cause.  Some rashes are widespread, while others are in just one area of the body.  Rashes can appear as reddened skin, red raised bumps, blisters, or scales. Rashes can itch and cause swelling.  Rashes can make the skin appear dry, leathery, or crusty.

Diagnosis

A doctor can diagnose a rash by examining your skin.  Blood tests, allergy testing, skin cultures, or a biopsy may be used to help determine the cause of your rash.

Treatment

The treatment for a rash depends on its cause and severity.  Common treatments include over-the-counter or prescription medications, lotions, or powders.

Prevention

You can prevent skin rashes by avoiding the substances that cause them.  Practice good hand washing.  Keep your skin clean and dry.  If you suspect that you have allergies, an allergist can perform skin testing to identify the substances to which you are allergic.

Complications

Secondary infection is a complication that can result from open areas in the skin caused by itching.  Signs of infection include red streaks, increasing redness, swelling, pain, or fever.  Call your doctor if you suspect that you have a skin infection.