We all experience itching in the armpit (axilla) now and then. Most of the time it is not a problem but just a temporary irritation and not due to any serious medical condition. However, persistent or frequent itching of the armpits, especially where there is a rash or other lesion, needs to be investigated from a medical perspective. There are several conditions where itching of the armpits may occur. This itching may be isolated to the armpits only or be part of itching elsewhere on the body.
Causes of Itchy Armpits
The causes of itchy armpits may vary from everyday lifestyle factors to serious medical conditions and skin diseases. Itching is only a symptom of some underlying problem. When itchy armpits are a temporary issue and does not recur again then it is usually not a cause for any concern. In fact, there may be no clearly identifiable cause in these instances. Various conditions like contact dermatitis and psoriasis which can cause an itchy skin rash anywhere on the body also needs to be considered as possible causes but are not discussed in detail below.
1. Infrequent Washing
The armpits is laden with sweat and oil glands as well as follicles of thicker hairs in adults. Being shielded from adequate ventilation due to its anatomical structure and clothing, means that this area is prone to irritants produced by the body, as well as substances applied to the area such as deodorants.
Dead skin cells, sweat and hair oils accumulate in the armpits and if not removed with frequent bathing, it can irritate the skin and thereby lead to itching. However, it is important to note that excessive washing, with strong scented and antibacterial soaps in addition to scrubbing vigorously can also irritate and damage the skin thereby leading to itching.
2. Excessive Sweating (Hyperhidrosis)
Hyperhidrosis is a condition where sweating is excessive. Sweating is necessary for the body to regulate temperature but when excessive it can lead to various skin symptoms such as itching and contribute to bad body odor. Sometimes this excessive sweating is isolated to only certain areas, with the armpits and back being among the commonly affected regions.
Injury to the armpits may occur in a number of different ways. The skin the armpits does not have underlying support like other regions. The overlying skin shields a triangular shaped hollow formed by the surrounding muscles. Therefore injury to the skin is easily caused by a host of different factors. Scratching for example can cause injury to skin anywhere on the body, but without adequate underlying tissue support a person may apply greater pressure.
Washing the area too vigorously can also cause injury. In addition, removal of armpit hair can also injure the skin in the area. Hot wax, shaving and even hair removal (depilatory) creams can cause mechanical and chemical injury. The area may become inflamed with redness, pain, tenderness and swelling. Itching may therefore also arise in the armpit area.
Read more on armpit irritation.
3. Contact Dermatitis
Contact dermatitis is a common skin condition that can affect the armpits. It leads to skin inflammation (dermatitis) when substances come into contact with the skin. These substances either acts as irritants or as allergens in people who are hypersensitive. Water, soap, shampoo, perfume, antiperspirant deodrant, body lotion and even sweat are common triggers. In addition, scratching due to the itchiness further exacerbates the condition.
The signs and symptoms of contact dermatitis includes excessive dryness of the skin, scaling, redness and itching. The symptoms usually subside if further exposure to the irritant or allergen is avoided. However, in severe cases it is often necessary to use medication like antihistamines, topical corticosteroids and emollients. In terms of allergic contact dermatitis it is important to prevent further exposure to the trigger substance.
4. Candida Infection
Candida albicans is an yeast that normally lives on the human skin but its population is kept within limits. In conditions with low immunity such as diabetes, cancer, AIDS, blood disorders, chemotherapy, corticosteroid therapy, these yeasts may overgrow. The affected areas are usually moist, warm and dark and therefore mainly found in the cavities like the mouth and vagina.
Less commonly, candida yeast can cause a fungal infection of the skin. This is more likely to occur when there is a break in the skin, recurrent chaffing and particularly in areas that are poorly ventilated, warm and dark. The armpits, groin and region under the breast in woman tend to be more commonly affected with yeast skin infections. The skin is broken, raw, moist and swollen. There may at times also be bleeding if scratched vigorously.
Read more on skin yeast infections.
Hidradenitis suppurativa is inflammation of apocrine (scent) glands, a special form of sweat glands responsible for the odor of the body. From an unknown reason, these glands become clogged. The secretions build up within the glands and form cysts that get infected, usually by Staphylococcus aureus. After several hours or days, the cysts burst and drain clear or yellow fluid. The inflammation leads to scarring of the skin tissue. The process may continue for several years. The cysts may appear in the armpits, groin or under breasts.
Treatment of hidradenitis suppurativa includes:
- Antibiotics (oral) or topical antimicrobial ointments.
- Injections of anti-inflammatory drugs.
- Surgical drainage or excision of cysts.
Prevention. Hidradenitis suppurativa is not caused by poor hygiene. Underarm shaving has to be avoided and the area must kept dry by wearing airy clothes.
6. Fox-Fordyce Disease
Fox-Fordyce disease is a rare disease resembling hidradenitis suppurativa and occurs mainly in young women (13-35 years of age). The sweat glands become clogged, and small itchy bumps appear under the arm and/or in the groin. Treatment is similar to that of hidradenitis suppurativa.
7. Other Causes
Sometimes itchy armpits occur with enlarged lymph nodes in armpits. This is seen in conditions like Paget disease of the breast (cancer). Disorders that cause generalized itching may also affect the armpits. These disorders include senile pruritus, heat rash, kidney and liver diseases, allergies, adverse effects to medications, skin or intestinal parasites, contact dermatitis, internal cancer.