Most commonly affects women aged 13–35 years, approximately puberty through their prime. Some reports show affected women to men at 9:1. Rare cases have been shown to affect post-menopausal women, children, and men. Incident report is currently unknown. Although rare, men and children have been shown to be affected. Heat, humidity, stress, and exercise have been shown to worsen symptoms. Rate of incidence is currently unknown. Fox-Fordyce has also been shown to be severe during menstruation and spontaneously disappear during pregnancy

Several triggering factors should be taken into consideration:

- Obesity is an exacerbating rather than a triggering factor, through mechanical irritation, occlusion, and maceration.

- Tight clothing, and clothing made of heavy, non-breathable materials.

- Deodorants, depilation products, shaving of the affected area – their association with hidradenitis suppurativa is still an ongoing debate amongst researchers.

- Drugs, in particular oral contraceptives (i.e., oral hormonal birth control; "the pill") and lithium.

- Hot and especially humid climates (dry/arid climates often cause remission).

In stage III disease, fistulae left undiscovered, undiagnosed, or untreated, can lead to the development of squamous cell carcinoma, a rare cancer, in the anus or other affected areas. Other stage III chronic sequelae may also include anemia, multilocalized infections, amyloidosis, and arthropathy. Stage III complications have been known to lead to sepsis, but clinical data is still uncertain.

Exact cause of Fox-Fordyce is currently unknown. Studies have not been able to confirm if apocrine gland duct obstruction is required for development. It is speculated that gland duct rupture causes inflammation. Inflammatory response includes white blood cells.

The Mayo Clinic suggests the following: antibiotics (generally the lowest side effect profile compared to other treatments); corticosteroids (e.g., prednisone); but corticosteroids have many side effects, including "moon face" for the duration of the medication's trial usage, as well as unwanted hair growth for females and/or osteoporosis with long-term use. Tumor necrosis factor (TNF)-alpha inhibitors like infliximab (Remicade) and adalimumab (Humira) have shown promise for some, but they should probably be considered a third-line treatment, as treatment is associated with increased risk of infection, heart failure and certain cancers. Surgery is also available for those overwhelmed by the condition, but it will not cure the condition, just relieve the skin-related issues for a while. The disease is pernicious and is almost always guaranteed to return, if not in the same spot where the surgery was performed.

Some products for adult acne may help relieve some symptoms for hidradenitis sufferers, although there is no guarantee it will work in all or even most individuals. Birth control Medication may relieve some symptoms for women; there is a hormonal treatment for men as well but that has not proven to be safe or effective as of yet.

Alternative treatments include alpha hydroxy acids (naturally available in small amounts in citrus fruits), Azelaic acid, and zinc. It is not thought that they are as effective as standard medical treatment but they tend to have less side effects. Some suggest tea tree oil and a specific strain of brewer's yeast, called CBS 5926. However, the former can cause contact dermatitis for some as well as breast development in teenage boys and should not be used if one suffers from rosacea as well due to it making the symptoms of that strand of acne worse; the latter (CBS 5962) can cause migraines and intestinal issues for some. None of these have been formally tested by the FDA so beware the risk you take when you forgo traditional Western medicine for herbal supplements.

Hidradenitis suppurativa is a chronic inflammatory skin condition, considered a member of the acne family of disorders. It is sometimes called acne inversa. The first signs of HS are small bumps on the skin that resemble pimples, cysts, boils, or folliculitis. As the disease progresses and abscesses reoccur, they become larger and more painful; eventually tunnels of scar tissue connect the lesions. These lesions may open up if they become too enlarged and drain bloodstained pus. One risk factor is age; HS usually first appears during the 20s and early 30s. The condition is much more common in women than in men but is usually more serious and debilitating in men. Other associated conditions include obesity, diabetes, metabolic syndrome, arthritis, acne, and other inflammatory disorders. Early diagnosis of this disease is very important to decrease the number of flares, pain, and discomfort.

Chromhidrosis (also referred to as "colored sweat") is a rare condition characterized by the secretion of colored sweat. It is caused by the deposition of lipofuscin in the sweat glands. Cases of red, blue, green, yellow, pink, and black sweat have been reported. Usually chromhidrosis affects the apocrine glands, mainly on the face and underarms. A limited number of treatment options exist, including regular application of Capsaicin cream and prolonged relief may be provided by botulinum toxin treatment. Chromogenic pigments produced by bacteria ("Corynebacterium" in particular) are implicated in this condition but their exact role still requires careful microbiological elucidation. Chromhidrosis of the eccrine glands is rare, it occurs mainly after the ingestion of certain dyes or drugs.

As many as 90% of Americans and 92% of teenagers use antiperspirants or deodorants. In 2014, the global market for deodorants was estimated at 13.00 billion USD with a compound annual growth rate of 5.62% between 2015 and 2020.

Prickly heat can be prevented by avoiding activities that induce sweating, using air conditioning to cool the environment, wearing light clothing and in general, avoiding hot and humid weather. Frequent cool showers or cool baths with mild soap can help to prevent heat rash.

A cutaneous condition is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment.

Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying causes and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology (chronic blistering conditions), cause (skin conditions resulting from physical factors), and so on.

Clinically, the diagnosis of any particular skin condition is made by gathering pertinent information regarding the presenting skin lesion(s), including the location (such as arms, head, legs), symptoms (pruritus, pain), duration (acute or chronic), arrangement (solitary, generalized, annular, linear), morphology (macules, papules, vesicles), and color (red, blue, brown, black, white, yellow). The diagnosis of many conditions often also requires a skin biopsy which yields histologic information that can be correlated with the clinical presentation and any laboratory data. The introduction of cutaneous ultrasound has allowed the detection of cutaneous tumors, inflammatory processes, nail disorders and hair diseases.

Exogenous ochronosis can be caused from long-term usage of certain "skin lightening" products, even if the hydroquinone is in amounts as small as 2%.

Skin lightening products are still prevalent in many parts of the world. This may be due to aesthetic or social standing reasons, in areas where a lighter skin tone is considered to be a sign of wealth or beauty.

As well, skin-lightening creams containing compounds such as hydroquinone are commonly used to help with hyperpigmentation disorders such as melasma.

Hydroquinone is the compound most frequently used in skin whitening products. Due to concerns about its side effects, it was almost banned by the FDA in 2006, as there were medical issues of carcinogenicity and reports of disfiguring ochronosis. In the European Union hydroquinone has been banned in cosmetic creams since 2000.

Long-term use of creams containing this compound may lead to exogenous ochronotic lesions. The duration of the use is directly proportional to the risk of developing the condition with most cases being after years of use.

Around 10–15 million skin lightening products are sold annually, with Japan being the major buyer.

Many conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square meters, and is made of three distinct layers: the epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin. Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. In the embryo, the epidermis, hair, and glands form from the ectoderm, which is chemically influenced by the underlying mesoderm that forms the dermis and subcutaneous tissues.

The epidermis is the most superficial layer of skin, a squamous epithelium with several strata: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale. Nourishment is provided to these layers by diffusion from the dermis, since the epidermis is without direct blood supply. The epidermis contains four cell types: keratinocytes, melanocytes, Langerhans cells, and Merkel cells. Of these, keratinocytes are the major component, constituting roughly 95 percent of the epidermis. This stratified squamous epithelium is maintained by cell division within the stratum basale, in which differentiating cells slowly displace outwards through the stratum spinosum to the stratum corneum, where cells are continually shed from the surface. In normal skin, the rate of production equals the rate of loss; about two weeks are needed for a cell to migrate from the basal cell layer to the top of the granular cell layer, and an additional two weeks to cross the stratum corneum.

The dermis is the layer of skin between the epidermis and subcutaneous tissue, and comprises two sections, the papillary dermis and the reticular dermis. The superficial papillary dermis with the overlying rete ridges of the epidermis, between which the two layers interact through the basement membrane zone. Structural components of the dermis are collagen, elastic fibers, and ground substance. Within these components are the pilosebaceous units, arrector pili muscles, and the eccrine and apocrine glands. The dermis contains two vascular networks that run parallel to the skin surface—one superficial and one deep plexus—which are connected by vertical communicating vessels. The function of blood vessels within the dermis is fourfold: to supply nutrition, to regulate temperature, to modulate inflammation, and to participate in wound healing.

The subcutaneous tissue is a layer of fat between the dermis and underlying fascia. This tissue may be further divided into two components, the actual fatty layer, or panniculus adiposus, and a deeper vestigial layer of muscle, the panniculus carnosus. The main cellular component of this tissue is the adipocyte, or fat cell. The structure of this tissue is composed of septal (i.e. linear strands) and lobular compartments, which differ in microscopic appearance. Functionally, the subcutaneous fat insulates the body, absorbs trauma, and serves as a reserve energy source.

Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying etiologies and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology (chronic blistering conditions), etiology (skin conditions resulting from physical factors), and so on. Clinically, the diagnosis of any particular skin condition is made by gathering pertinent information regarding the presenting skin lesion(s), including the location (such as arms, head, legs), symptoms (pruritus, pain), duration (acute or chronic), arrangement (solitary, generalized, annular, linear), morphology (macules, papules, vesicles), and color (red, blue, brown, black, white, yellow). Diagnosis of many conditions often also requires a skin biopsy which yields histologic information that can be correlated with the clinical presentation and any laboratory data.

"Miliaria pustulosa" describes pustules due to inflammation and bacterial infection. Miliaria pustulosa is preceded by another dermatitis that has produced injury, destruction, or blocking of the sweat duct.

Ochronosis is a syndrome caused by the accumulation of homogentisic acid in connective tissues. It was first described by Rudolf Virchow in 1865. The condition was named after the yellowish (ocher-like) discoloration of the tissue seen on microscopic examination. However, macroscopically the affected tissues appear bluish grey because of a light-scattering phenomenon known as the Tyndall effect. The condition is most often associated with alkaptonuria but can occur from exogenous administration of phenol complexes like hydroquinone.

Body odor may be reduced or prevented or even aggravated by using deodorants, antiperspirants, disinfectants, underarm liners, triclosan, special soaps or foams with antiseptic plant extracts such as ribwort and liquorice, chlorophyllin ointments and sprays topically, and chlorophyllin supplements internally. Although body odor is commonly associated with hygiene practices, its presentation can be affected by changes in diet as well as the other factors.

Diseases of the skin include skin infections and skin neoplasms (including skin cancer).

Apocrine gland carcinoma is a cutaneous condition characterized by skin lesions which form in the axilla or anogenital regions.

Schöpf–Schulz–Passarge syndrome (also known as "eyelid cysts, palmoplantar keratoderma, hypodontia, and hypotrichosis") is an autosomal recessive condition with diffuse symmetric palmoplantar keratoderma, with the palmoplantar keratoderma and fragility of the nails beginning around age 12. In addition to palmoplantar keratoderma, other symptoms include hypodontia, hypotrichosis, nail dystrophies, and eyelid cysts (apocrine hidrocystomas). Patients may also develop syringofibroadenoma and squamous cell carcinomas.

It was characterized in 1971.

It has been associated with WNT10A.

An Apocrine nevus is an extremely rare cutaneous condition that is composed of hyperplastic mature apocrine glands.

A folliculosebaceous-apocrine hamartoma, also known as "follicular-apocrine hamartoma", is a benign proliferation of the folliculosebaceous-apocrine unit.

Many myths are given regarding the possible causes of baldness and its relationship with one's virility, intelligence, ethnicity, job, social class, wealth, etc. While skepticism may be warranted in many cases due to a lack of scientific validation, some claims may have a degree of underlying truth and are supported by research.

A 50% chance exists for a person to share the same X chromosome as his maternal grandfather. Because women have two X chromosomes, they have two copies of the androgen receptor gene, while men only have one. However, a person with a balding father also has a significantly greater chance of experiencing hair loss.

Because it increases testosterone levels, many Internet forums have put forward the idea that weight training and other forms of exercise increase hair loss in predisposed individuals. Although scientific studies do support a correlation between exercise and testosterone, no direct study has found a link between exercise and baldness. However, a few have found a relationship between a sedentary life and baldness, suggesting some exercise is beneficial. The type or quantity of exercise may influence hair loss.

Testosterone levels are not a good marker of baldness, and many studies actually show paradoxical low testosterone in balding persons, although research on the implications is limited.

Emotional stress has been shown to accelerate baldness in genetically susceptible individuals.

Stress due to sleep deprivation in military recruits lowered testosterone levels, but is not noted to have affected SHBG. Thus, stress due to sleep deprivation in fit males is unlikely to elevate DHT, which is one cause of male pattern baldness. Whether sleep deprivation can cause hair loss by some other mechanism is not clear.

Levels of free testosterone are strongly linked to libido and DHT levels, but unless free testosterone is virtually nonexistent, levels have not been shown to affect virility. Men with androgenic alopecia are more likely to have a higher baseline of free androgens. However, sexual activity is multifactoral, and androgenic profile is not the only determining factor in baldness. Additionally, because hair loss is progressive and free testosterone declines with age, a male's hairline may be more indicative of his past than his present disposition.

Many misconceptions exist about what can help prevent hair loss, one of these being that lack of sexual activity will automatically prevent hair loss. While a proven direct correlation exists between increased frequency of ejaculation and increased levels of DHT, as shown in a recent study by Harvard Medical School, the study suggests that ejaculation frequency may be a sign, rather than a cause, of higher DHT levels. Another study shows that although sexual arousal and masturbation-induced orgasm increase testosterone concentration around orgasm, they reduce testosterone concentration on average (especially before abstinence) and because about 5% of testosterone is converted to DHT, ejaculation does not elevate DHT levels.

The only published study to test correlation between ejaculation frequency and baldness was probably large enough to detect an association (1390 subjects) and found no correlation, although persons with only vertex androgenetic alopecia had had fewer female sexual partners than those of other androgenetic alopecia categories (such as frontal or both frontal and vertex). One study may not be enough, especially in baldness, where there is a complex with age. Marital status has been shown in some studies to influence hair loss in cross-sectional studies (NHANES1).

The decision to observe or treat a nevus may depend on a number of factors, including cosmetic concerns, irritative symptoms (e.g., pruritus), ulceration, infection, and concern for potential malignancy.

Ionizing radiation-induced cutaneous conditions result from exposure to ionizing radiation.

- Acute radiodermatitis

- Chronic radiation keratosis

- Chronic radiodermatitis

- Eosinophilic, polymorphic, and pruritic eruption associated with radiotherapy

- Fluoroscopy burn

- Radiation acne

- Radiation cancer

- Radiation dermatitis (radiodermatitis)

- Radiation recall reaction

- Radiation-induced erythema multiforme

- Radiation-induced hypertrophic scar

- Radiation-induced keloid

- Radiation-induced morphea

The term "nevus" is applied to a number of conditions caused by neoplasias and hyperplasias of melanocytes, as well as a number of pigmentation disorders, both hypermelanotic (containing increased melanin, the pigment responsible for skin color) and hypomelanotic (containing decreased melanin).

Androgenic alopecia is typically experienced as a "moderately stressful condition that diminishes body image satisfaction". However, although most men regard baldness as an unwanted and distressing experience, they usually are able to cope and retain integrity of personality.

Although baldness is not as common in women as in men, the psychological effects of hair loss tend to be much greater. Typically, the frontal hairline is preserved, but the density of hair is decreased on all areas of the scalp. Previously, it was believed to be caused by testosterone just as in male baldness, but most women who lose hair have normal testosterone levels.