Seborrheic Dermatitis

Inflammatory ICD: L21

Also known as: Seborrhoeic Eczema, Dandruff, Cradle Cap (infantile)

Description

Seborrheic dermatitis is a common chronic relapsing inflammatory condition affecting sebum-rich areas of the skin. It is mediated by Malassezia yeast and characterised by erythematous patches with greasy yellowish scales. Dandruff is considered a mild non-inflammatory variant limited to the scalp.

Symptoms

  • Erythematous patches with greasy yellow-white scales
  • Scalp flaking (dandruff) with pruritus
  • Nasolabial folds, eyebrows, behind ears affected
  • Blepharitis (eyelid involvement)
  • Chest and intertriginous areas in extensive cases

Causes & Triggers

  • Malassezia yeast overgrowth and inflammatory response to its metabolites
  • Sebaceous gland activity (lipid-rich environment)
  • Immune dysregulation (more severe in immunocompromised)
  • Neurological association (Parkinson's disease)
  • Stress, fatigue, and seasonal flares (winter)

Severity Classification

Mild Scalp flaking (dandruff) with minimal erythema
Moderate Facial and scalp involvement with visible scales and erythema
Severe Widespread facial, scalp, and truncal involvement

Treatment Ladder

  1. 1 Mild scalp: Antifungal shampoo (ketoconazole 2%, zinc pyrithione)
  2. 2 Face: Low-potency topical corticosteroids or topical antifungals
  3. 3 Moderate: Combination antifungal + anti-inflammatory
  4. 4 Maintenance: Intermittent antifungal shampoo or cream 1–2× per week
  5. 5 Severe / Refractory: Oral antifungal (itraconazole) short course

Relevant Compounds

Aloe Vera

Soothing adjunct for irritated skin

Aloe vera is derived from the inner gel of Aloe barbadensis miller leaves. It contains over 75 activ…

Hydrocortisone

Mild steroid for facial involvement

Hydrocortisone is a low-potency topical corticosteroid identical to endogenous cortisol. It is the m…

Niacinamide

Anti-inflammatory and barrier support

Niacinamide is the physiologically active amide form of vitamin B3. It is a versatile, well-tolerate…

Panthenol

Calming and barrier repair

Panthenol (D-panthenol or dexpanthenol) is the alcohol analogue of pantothenic acid (vitamin B5). Up…

Salicylic Acid

Keratolytic — loosens and removes scales

Salicylic acid is a lipophilic beta hydroxy acid with keratolytic, comedolytic, and mild anti-inflam…

Tea Tree Oil

Antifungal activity against Malassezia

Tea tree oil is a volatile essential oil derived from the Australian plant Melaleuca alternifolia. I…

Zinc PCA

Antimicrobial and sebum-regulating

Zinc PCA is the zinc salt of pyrrolidone carboxylic acid (PCA), a natural component of the skin's Na…

Recommended Drugs

Cortaid OTC hydrocortisone for facial flares (short-term use)

Suggested Cosmetics

Cetaphil Gentle Skin Cleanser Gentle non-stripping cleanser Cipla Excela Moisturiser Lightweight moisturiser that won't exacerbate oiliness Deconstruct Pore Control Serum — 2% Salicylic Acid + 3% Niacinamide Niacinamide anti-inflammatory with salicylic acid exfoliation Episoft AC Moisturiser with SPF 30 Oil-free moisturiser that won't aggravate oiliness Mamaearth Tea Tree Face Wash Tea tree oil has antifungal properties against Malassezia Minimalist 10% Niacinamide Face Serum Anti-inflammatory care for seborrheic-prone skin

Lifestyle Tips

  • Use medicated shampoos 2–3× per week, leaving on for 5 minutes before rinsing
  • Alternate between different antifungal shampoos to prevent resistance
  • Avoid heavy oily hair products
  • Manage stress — flares correlate with stress levels
  • Continue maintenance therapy even during remission periods

When to Refer

  • Resistant to standard topical therapy
  • Widespread or atypical distribution
  • Immunocompromised patients with severe disease
  • Diagnostic uncertainty (psoriasis, tinea, lupus overlap)