30th July 2026

Irritant Contact Dermatitis

Background

Contact dermatitis also known as contact eczema, is an exogenous inflammatory skin disorder. The two main subtypes of the condition are irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). Irritant contact dermatitis is a skin reaction that occurs upon exposure to environmental substances or factors which damage the skin barrier. Mainstay treatment involves avoidance of the irritant and emollients to maintain the skin barrier function. Prognosis is good if the irritant is avoided with restoration of healthy skin in 4 weeks. 

Epidemiology 

ICD accounts for approximately 80% of occupation related contact dermatitis and is the more common subtype. Prevalence of ICD ranges between 0.4 to 4% of the population, however this is likely an underestimate as a large proportion of patients do not seek medical attention. The condition has a female predominance. 

Aetiology

The exact pathogenesis of the condition is unknown, however there appears to be disruption of the epidermal layer by the irritant which leads to increased skin permeability and transepidermal water loss allowing the chemical/irritant to penetrate. Keratinocyte injury with cytokine release e.g. interleukin 1-alpha, interleukin-1-beta, IL-6 and TNF-alpha triggers an inflammatory response.

Risk factors

• Young age
• Female
• Atopy

Common irritants

Table 6: Common irritants in ICD

Environmental factors such as temperature and humidity can also have an impact. 

Clinical manifestation

Areas commonly affected are the face, dorsum of the hands and finger webs due to relatively thinner stratum corneum. 

Acute ICD: singular exposure to the offending agent

• Burning/pain
• Localised erythema (redness) 
• Vesicles (blistering)
• Oedema (swelling)

Chronic ICD: multiple exposures to irritant

• Erythema (redness)
• Scale
• Lichenification
• Hyperkeratosis
• Fissures (cracking of the skin)

Diagnosis is largely clinical, based on a history of exposure to the irritant followed by the development of dermatitis.

Investigations

• Patch testing: help differentiate between ICD and ACD
• Histological examination: useful to differentiate from other inflammatory dermatoses

Differential diagnosis

• Allergic contact dermatitis
• Atopic dermatitis
• Psoriasis
• Tinea 
• Scabies 

Medical/surgical management 

• Identification of trigger
• Avoidance of future exposure
  • Minimise contact with irritants
  • Use of gloves
  • Lukewarm water
  • Small amounts of soap-free skin cleansers
  • Drying hands thoroughly
• Treatment of existing dermatitis 
  • Emollients: reduce transepidermal water loss and restore the skin barrier
  • Topical corticosteroids
  • Calcineurin inhibitors 
  • Phototherapy 

Complications  

• Disseminated secondary eczema
• Lichenification
• Secondary bacterial infection