The Management of Itchy Skin
R. Vender, MD, FRCPC
Division of Dermatology McMaster University, and
Director of Dermatrials Research, Hamilton, Canada
Itchy skin is a very common complaint seen in family practice as well as in
dermatology practice. Causes of itchiness are extremely diverse and wide spread.
A subset of nociceptive C neurons is responsible for the transmission of itch or
pruritus, and these mediators (mainly histamine) can act centrally or peripherally.
Skin disease that can mediate itchiness can originate in the skin or even in the
central or peripheral nervous systems.
Dermatologic Diseases With Pruritus
- Arthropod bites
- Schistosomal cercarial dermatitis (swimmer’s itch)
- Atopic dermatitis
- Stasis dermatitis
- Irritant or allergic contact dermatitis
- Lichen simplex chronicus
- Psoriasis, parapsoriasis
- Prurigo nodularis
- Drug hypersensitivity
- Bullous disease, e.g., dermatitis herpetiformis, bullous pemphigoid
- Pityriasis rubra pilaris
- Polymorphous light eruption
- Eosinophilic pustular folliculitis (Ofuji’s disease)
- Prurigo pigmentosa
- PUPPP (pruritic urticaria papules and plaques of pregnancy)
- Fungal infections, e.g., inflammatory tinea
- Bacterial infections, e.g., folliculitis
- Viral infections, e.g., varicella
- Cutaneous T-cell lymphoma
Hereditary or Congenital
- Darier-White disease
- Hailey-Hailey disease
- Inflammatory linear verrucous epidermal nevus (ILVEN)
- Xerosis, eczema craquele
- Senile pruritus
- Anogenital pruritus
- Itching in scars
- Nostalgia paresthetica
- Amyloidosis, mucinosis
- Postburn and poststroke pruritus
- Fiberglass dermatitis
- Aquagenic pruritus
Categories of Pruritus Therapy
Identification and treatment of the underlying disease
- Patient education
- Elimination of provocative factors
- Topical therapy
- Corticosteroids for inflammatory conditions
- Calcineurin inhibitors, e.g., tacrolimus (Protopic®) and pimecrolimus (Elidel®)
- Crotamiton (Eurax®)
- Systemic therapy
- Sedation can be of benefit, especially in eczema
- Physical modalities: e.g., phototherapy
Treatment of Specific Skin Disorders
Moisturizing is extremely important for replenishing the skin’s water content and preventing water loss. Maintaining the
barrier to keep out exacerbating factors from the skin, such as the external environment, is beneficial. Moisturizers should
contain the following: emollients, humectants, occlusives, soothing agents and anti-irritants.
Oral antihistamines, especially those with sedating properties, e.g., hydroxyzine (Atarax®) or diphenhydramine (Benadryl®)
may provide benefit for patients with pruritus. An antidepressant with potent antihistaminic properties, doxepin (Sinequan®),
can also be useful. The role of histamine in eczema is questionable. Alpha hydroxy acids can reduce scaling and roughness.
Histamine release has a central role in urticaria. There are many causes of urticaria that can be investigated by an allergist.
Oral antihistamines, either sedating or nonsedating, are beneficial. Nonsedating antihistamines, such as loratadine (Claritin®),
desloratadine (Aerius®), or fexofenadine (Allegra®), can be used in combination with sedating antihistamines at bedtime.
- The cold, dry air of Canadian winters increases transepidermal water loss and causes xerosis (severely dry skin).
- As we heat our homes, especially with electric heat, it reduces the humidity in the air.
- The skin tries to maintain an equilibrium, also causing an increase in transepidermal water loss.
- All ages can be affected.
- Can exacerbate underlying skin diseases associated with pruritus, which in turn can exacerbate pruritus further.
- Minimize soap. Nonsoap cleansers can be helpful (e.g., emulsifying ointment, Spectrogel®, Cetaphil®).
- Petrolatum depositing moisturizing body washes and in-shower moisturizers (e.g., Olay® Ribbons) can be helpful .
- Moisturizing after a bath is extremely important.
There is new evidence to show that moisturizers containing niacinamide and glycerin (e.g., Olay® Quench) not only hydrate the skin, but improve the skin's resistance to external factors and improve the barrier function. Glycerin is required for moisturizers to work quickly and add moisture to the skin, but the niacinamide helps to sustain that benefit over a longer period of time.
- Treat underlying cause of pruritus
- petrolatum depositing in-shower body washes helpful
- beneficial for most itchy disorders
- sedating and nonsedating (sedating is necessary for atopics)
- helpful for symptomatic relief
- Topical 5% doxepin cream
- useful in neurodermatitis
- Capsaicin 0.025% cream, e.g., Zosterix®
- used in postherpetic neuralgia
- Topical menthol and camphor lotion
- best in adults
- not well tolerated in children
- Crotamiton cream or lotion
- Topical anesthetics such as EMLA®
- useful in neurodermatitis
- Calcineurin inhibitors such as tacrolimus or pimecrolimus
- approved for atopic dermatitis
- Systemic therapy such as ultraviolet B or narrowband
- UVB or PUVA
- pruritus in pregnancy or systemic causes of itchiness
- Topical corticosteroids
- most inflammatory skin diseases
- Topical Vitamin D3 analogs, e.g., Dovonex®
- Cholestyramine and colestipol resins used to control pruritus in patients with cholestatic liver disease.
The causes and differential diagnoses are as diverse for pruritus as the treatment and management are nonspecific. This makes
the workup of nonspecific itch difficult. With careful history and physical exam, as well as some laboratory investigations,
most serious disorders can be ruled out and the patient's itch can be relieved.
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