Diagnosis is largely based on patient description and relevant details about recent surgeries, hip injuries, or repetitive activities that could irritate the nerve. Examination checks for sensory differences between the affected leg and the other leg. Accurate diagnosis may require an abdominal and pelvic examination to exclude problems in those areas.

Electromyographic (EMG) nerve-conduction studies may be required. X-rays may be needed to exclude bone abnormalities that might put pressure on the nerve; likewise CT or MRI scans to exclude soft tissue causes such as a tumor.

Therapy for notalgia paresthetica is directed at controlling symptoms, as no cure exists for the condition. Available treatments include local anesthetics, topical capsaicin, topical corticosteroids, hydroxyzine, oxcarbazepine, palmitoylethanolamide and gabapentin. Paravertebral nerve block and botulinum toxin injections may also be helpful.

Some patients treated with low concentration topical capsaicin reported pain, burning, or tingling sensations with treatment, and symptoms returned within a month of ceasing treatment. Oxcarbazepine was reported to reduce the severity of symptoms in a few cases. One patient has been treated with "paravertebral nerve blocks, with bupivacaine and methylprednisolone acetate injected into the T3–T4 and T5–T6 intervertebral spaces" Hydroxyzine has also been used with considerable success in some cases as long as the pills are used daily.

High concentration topical capsaicin (8%, Qutenza) have been shown to be highly effective in treating neuropathic itch in some patients (including notalgia paresthetica) as well as in a recent proof-of-concept study, but this remains to be confirmed in randomised controlled trials.

Most recently intradermal injections of botulinum toxin type A (Botox) have been tried with some success. Even though botulinum normally wears off in three to six months, the treatment appears to be long term, and it has been theorised that botulinum type A effects lasting change in pain signaling. Unfortunately, repeated injections have been associated with diminished movement ability of the upper back and arms and its recommendation as a treatment has therefore become less popular.

Treatment varies. In most cases, the best treatment is to remove the cause of compression by modifying patient behavior, in combination with medical treatment to relieve inflammation and pain. Whatever the cause, typical treatment takes several weeks to months—depending on the degree of nerve damage. Typical treatment options include:

- Active Release Technique (ART) soft tissue treatment

- Wearing looser clothing and suspenders rather than belts

- Weight loss if obesity is present

- Non-steroidal anti-inflammatory drugs (NSAIDs) to reduce inflammatory pain if pain level limits motion and prevents sleep

- Reducing physical activity in relation to pain level. Acute pain may require absolute bed rest

- Deep tissue massage to reduce tension in the gluteal muscles, most commonly the gluteus maximus. The tensor fasciae latae may also be implicated.

The lateral cutaneous nerve of the thigh can occasionally be damaged during laparoscopic hernia repair, or scarring from the operation can lead to meralgia paraesthetica.

For lower pain levels, treatment may involve having the patient:

- Seek appropriate physical therapy, such as stretching and massage, which plays a large role in the management of pain

- Learn to perform inguinal ligament stretching (from a physical therapist or from a YouTube video) which can rapidly relieve symptoms

- Use rest periods to interrupt long periods of standing, walking, cycling, or other aggravating activity

- Lose weight, and exercise to strengthen abdominal muscles

- Wear clothing that is loose at the upper front hip area

- Apply heat, ice, or electrical stimulation

- Take nonsteroidal anti-inflammatory medications for 7–10 days

- Remove hair in affected area (shave)

- Lidocaine patches (must shave area first)

- Titanium dioxide patches to interfere with the electrostatic effect of the nerves on the surface of the skin

Pain may take significant time (weeks) to stop and, in some cases, numbness persists despite treatment. In severe cases, the physician might perform a local nerve block at the inguinal ligament, using a combination of local anaesthetic (lidocaine) and corticosteroids to provide relief that may last several weeks. Pain modifier drugs for neuralgic pain (such as amitriptyline, carbamazepine or gabapentin) may be tried, but are often not as helpful in the majority of patients.

Persistent and severe cases may require surgery to decompress the nerve or, as a last resort, to resect the nerve. The latter treatment leaves permanent numbness in the area.

Notalgia paraesthetica (NP) or notalgia paresthetica (also known as "Hereditary localized pruritus", "Posterior pigmented pruritic patch", and "Subscapular pruritus") is a chronic sensory neuropathy. Notalgia paraesthetica is a common localized itch, affecting mainly the area between the shoulder blades (especially the T2–T6 dermatomes) but occasionally with a more widespread distribution, involving the shoulders, back, and upper chest. The characteristic symptom is pruritus (itch or sensation that makes a person want to scratch) on the back, usually on the left hand side below the shoulder blade (mid to upper back). It is occasionally accompanied by pain, paresthesia (pins and needles), or hyperesthesia (unusual or pathologically increased sensitivity of the skin to sensory stimuli, such as pain, heat, cold, or touch), which results in a well circumscribed hyperpigmentation of a skin patch in the affected area.

Radial neuropathy is not necessarily permanent. The majority of radial neuropathies due to an acute compressive event (Saturday night palsy) do recover without intervention. If the injury is demyelinating (meaning only the myelin sheath surrounding the nerve is damaged), then full recovery typically occurs within 2–4 weeks. If the injury is axonal (meaning the underlying nerve fiber itself is damaged) then full recovery may take months or years, or may never occur. EMG and nerve conduction studies are typically performed to diagnose the extent and distribution of the damage, and to help with prognosis for recovery.

In order to diagnose radial nerve dysfunction, a doctor will conduct a physical examination. During the exam of the arm, wrist, and hand, the doctor will look for: difficulty straightening the arm at the elbow; trouble turning the arm outward; difficulty lifting the wrist; muscle loss or atrophy in the forearm; weakness of the wrist and/or fingers. In addition, tests may need to be conducted to confirm the doctors findings. These tests include: blood tests; MRI of the neck and shoulders to screen for other problems; nerve biopsy; nerve conduction tests; ultrasound of the elbow.

Approximately 280 million people globally, 4% of the population, have difficulty with itchiness. This is comparable to the 2–3% of the population suffering from psoriasis.

A variety of over-the-counter and prescription anti-itch drugs are available. Some plant products have been found to be effective anti-pruritics, others not. Non-chemical remedies include cooling, warming, soft stimulation.

Topical antipruritics in the form of creams and sprays are often available over-the-counter. Oral anti-itch drugs also exist and are usually prescription drugs. The active ingredients usually belong to the following classes:

- Antihistamines, such as diphenhydramine (Benadryl)

- Corticosteroids, such as hydrocortisone topical cream; "see" topical steroid

- Counterirritants, such as mint oil, menthol, or camphor

- Crotamiton (trade name Eurax) is an antipruritic agent available as a cream or lotion, often used to treat scabies. Its mechanism of action remains unknown.

- Local anesthetics, such as benzocaine topical cream (Lanacane)

Phototherapy is helpful for severe itching, especially if caused by renal failure. The common type of light used is UVB.

Sometimes scratching relieves isolated itches, hence the existence of devices such as the back scratcher. Often, however, scratching can intensify itching and even cause further damage to the skin, dubbed the "itch-scratch-itch cycle."

The mainstay of therapy for dry skin is maintaining adequate skin moisture and topical emollients.

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.

Urticaria is a vascular reaction of the skin characterized by the appearance of wheals, which are firm, elevated swelling of the skin. Angioedema, which can occur alone or with

urticaria, is characterized by a well-defined, edematous swelling that involves subcutaneous tissues, abdominal organs, or upper airway.

- Acquired C1 esterase inhibitor deficiency

- Acute urticaria

- Adrenergic urticaria

- Anaphylaxis

- Aquagenic urticaria

- Cholinergic urticaria

- Chronic urticaria (ordinary urticaria)

- Cold urticaria

- Dermatographism (dermographism)

- Episodic angioedema with eosinophilia (Gleich's syndrome)

- Exercise urticaria (exercise-induced urticaria)

- Galvanic urticaria

- Heat urticaria

- Hereditary angioedema (Quincke's edema)

- Localized heat contact urticaria

- Mast cell-independent urticaria

- Physical urticaria

- Primary cold contact urticaria

- Pressure urticaria (delayed pressure urticaria)

- Reflex cold urticaria

- Schnitzler syndrome

- Secondary cold contact urticaria

- Solar urticaria

- Systemic capillary leak syndrome

- Urticarial allergic eruption

- Urticaria-like follicular mucinosis

- Vibratory angioedema