Underarm skin rashes may result from infections, autoimmune disorders and exposure to allergens, according to Healthgrades. The rashes may also result from certain medications, acne and life-threatening conditions, including anaphylaxis and allergic purpura.
Allergens that may cause underarm rashes include cosmetics, chemicals from industries, poison ivy and food, notes Healthgrades. Bee stings, dyes and detergents are other allergens that can lead to underarm rashes. Shingles, impetigo, ringworm, strep throat and pityriasis rosea are some of the infections that may cause underarm skin rashes.
Other infections that may cause underarm rashes are eczema; Lyme disease, which is an inflammation that results from ticks; and meningitis, which is an inflammatory condition affecting the sac that surrounds the central nervous system. Psoriasis; Kawasaki disease, which is a condition that results in blood vessel swelling, rash and high body temperature among children; rheumatoid arthritis, which is an inflammatory condition of the joints; and systemic lupus erythematosus, constitute autoimmune disorders that may result in underarm rashes.
The fact that underarm rashes may signify a life-threatening underlying condition necessitates immediate medical attention when the condition occurs, in order to ensure early diagnosis and treatment of the cause, advises Healthgrades. This helps to prevent associated complications such as miscarriage, irreversible loss of hearing and paralysis.
Underarm rash is a skin condition that attacks the armpit skin, resulting in the skin reddening, swelling and blotching, states Healthgrades. Patients with underarm rashes may also experience, among other symptoms, headache, joint ache, difficulty breathing and facial inflammation.