What is underarm itch?
An underarm itch is a tickling, irritating sensation accompanied by the persistent need to scratch your underarm. The medical term for itching is pruritus. Redness, swelling, soreness, flaking and scarring may occur in the area of itchiness. Although scratching may temporarily relieve your symptoms, persistent scratching can worsen underarm itch symptoms and leave the affected skin susceptible to contamination and infection. With most cases of itching, it is best if you can refrain from scratching and leave the area alone to heal.
Causes of underarm itch are numerous and include insect bites, allergies, infections, and trauma. When wounds are healing they often start to itch, which is a sign of improvement. Chickenpox, an extremely common childhood illness, is accompanied by red, oozing blisters that cause intense itching. Eczema and contact dermatitis are potential causes, as are conditions such as head lice, scabies, and pinworm. An underarm itch may stem from a rash or ingrown hair that is caused by shaving. The underarm area is continuously warm and moist, making it an ideal environment for a variety of fungal skin infections.
Obstructive biliary disease, caused by a blockage of the bile ducts, is condition that causes severe itching. Chronic kidney disease can also cause generalized itching.
Most causes of underarm itch are fairly mild and should not be a cause for concern. However, your health care professional should evaluate itching that is sudden, severe or unusual. Itching caused by a serious food allergy can come on rapidly with a strong need to scratch. This type of itching may be symptomatic of a serious anaphylactic reaction, which impairs breathing and causes swelling, fainting, and vomiting, and is considered a medical emergency.
Sudden itching can be a sign of anaphylaxis, a severe, life-threatening allergic reaction to a food, chemical, or insect sting. Seek immediate medical care (call 911) if an itch is accompanied by symptoms such as swelling of the face, swelling or constriction of the throat, difficulty breathing, fainting, change in level of consciousness or alertness, or rash.
What other symptoms might occur with underarm itch?
Underarm itch may be accompanied by other symptoms, depending on the underlying disease, disorder or condition. Certain conditions that cause underarm itch may also involve other body systems.
Related localized symptoms that may occur along with underarm itch
Underarm itch may be accompanied by other localized symptoms including:
- Crusting or flaking skin
- Painful skin
- Redness, warmth or swelling
- Scale formation
- Tenderness or pain
Other symptoms that may occur along with underarm itch
Underarm itch may accompany symptoms related to other body systems including:
Serious symptoms that might indicate a life-threatening condition
In some cases, underarm itch may be a symptom of a life-threatening condition that should be evaluated immediately in an emergency setting. Seek immediate medical care (call 911) if you, or someone you are with, have underarm itch along with other serious symptoms including:
Change in level of consciousness or alertness, such as passing out or unresponsiveness
Joint pain and stiffness
Sudden swelling of the face, lips or tongue
Tightness or constriction in the throat
Worsening of symptoms despite treatment
What causes underarm itch?
Underarm itch may have many possible causes, including allergens (agents that cause allergies), infections, autoimmune disorders, or other causes such as stress.
Allergic causes of underarm itch
Underarm may be caused by contact dermatitis. Common triggers include:
Cosmetics, dyes or detergents
Industrial chemicals, such as those found in elastic, latex and rubber
Metallic substances (various metals, copper, wire)
Poison ivy or oak
Other allergic causes of underarm itch include:
Eczema (skin disorder causing scaly or blistering rashes that may be caused by allergy)
Food allergies (allergic reactions to certain foods)
Insect bite allergy such as a bee sting
Infectious causes of underarm itch
Underarm itch can also be caused by infections including:
Candidiasis (yeast infection)
Eczema (skin disorder causing scaly or blistering rashes that may be caused by infection)
Tinea corporis (dermatophyte infection)
Other causes of underarm itch
Underarm itch can be caused by other conditions such as:
Parasites, insects and arachnids that cause under arm itch
Under arm itch can be due to insects, parasites or arachnids that bite the skin or burrow in the skin including:
Mosquito bites (mosquitoes also carry parasitic diseases)
Serious or life-threatening causes of underarm itch
In some cases, underarm itch may be a symptom of a serious or life-threatening condition that should be evaluated immediately in an emergency setting. These include:
Anaphylaxis (life-threatening allergic reaction)
Chronic renal failure (also called chronic kidney disease)
Obstructive biliary disease (obstruction of the bile ducts)
Questions for diagnosing the cause of underarm itch
To diagnose your condition, your doctor or licensed health care practitioner will ask you several questions related to your itch including:
When did the itching begin?
Are you taking any medications?
Do you have any known allergies?
Do you feel otherwise healthy?
Have you tried any new products recently, such as soaps, perfumes, sprays or deodorants?
Have you spent a lot of time outdoors lately?
Does scratching make it better or worse?
An itch is not usually serious, but it’s important to determine its underlying cause and rule out a serious infection. Once the underlying cause of your itch is diagnosed, it is important for you to follow the treatment plan that you and your health care professional design specifically for you to reduce the risk of potential complications, including secondary infections, which may develop from scratching and related skin trauma.