What is underarm rash?

Rash is a symptom that causes the affected area of skin to turn red and blotchy and to swell. A rash may cause spots that are bumpy, scaly, flaky, or filled with pus. Rashes can vary in location, pattern and extent and may occur in any area of the body. A rash under your arm can have a variety of causes, and it may indicate something occurring around the underarm itself or suggest a systemic (body-wide) condition.

Contact dermatitis (skin inflammation) is caused by an adverse reaction to something that touches your skin, including chemicals found in a detergent, soap, or fragrance. You may develop a rash under your arm when wearing a shirt that was washed with a particular detergent or treated with a chemical. Metal, such as jewelry, can also cause underarm rash. Other forms of contact dermatitis include exposure to certain plants, such as poison oak or ivy, an animal bite, or an insect sting. Lyme disease is caused by tick bite, which can first display as a circle with a bull’s-eye pattern, then progress to a rash. Rocky Mountain spotted fever is another tick-borne condition that may start with a rash on the arms and legs, followed by a fever and other flu-like symptoms. A rash under the arm can also be attributed to an infection from an ingrown hair from shaving.

Allergies to food and medications are potentially serious sources of rash. Peanuts, shellfish, strawberries and avocados are just some of the foods that can trigger allergic reactions. These foods may cause mild reactions; however, in some cases reactions could develop into potentially life-threatening conditions characterized by vomiting, difficulty breathing, and swelling. Allergic purpura is a serious, often life-threatening allergic reaction that can cause a skin rash but can also affect the joints, gastrointestinal tract, and kidneys.

Rashes may also be associated with skin conditions such as eczema, psoriasis and impetigo. These are skin conditions that may flare up for a time, then resolve. Other causes for rash include autoimmune disorders that occur when the body is attacked by its own immune system, which normally serves to protect it from foreign invaders (antigens). Many viruses that occur during flu season, or those associated with childhood diseases, can produce rash.

Rashes can be caused by an allergic reaction to food, medications, or products such as lotions or detergents. These reactions can range from mild to potentially life threatening, especially if swelling and constriction of breathing occurs, which could indicate anaphylaxis. Seek immediate medical care (call 911) if a rash is accompanied by any serious symptoms, including swelling of the face, swelling or constriction of the throat, difficulty breathing, fainting, change in level of consciousness or alertness, or purple rash.

Seek prompt medical care

if a rash is persistent or causes you concern.

SYMPTOMS

What other symptoms might occur with underarm rash?

Underarm rash may be accompanied by other symptoms, depending on the underlying disease, disorder or condition. Certain conditions that cause underarm rash may also involve other body systems.

Related localized symptoms that may occur along with underarm rash

Underarm rash may be accompanied by other localized symptoms including:

CAUSES

What causes underarm rash?

Underarm rash may have many possible causes, including allergens (agents that cause allergies), infections, autoimmune disorders, or other causes such as stress.

Allergic or inflammatory causes of underarm rash

Underarm rash may be caused by contact dermatitis. Common triggers include:

... Read more about underarm rashcauses

Medical Reviewer: Cynthia Haines, MD Last Annual Review Date: Aug 11, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Skin, Hair and Nails


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