What is the treatment for eczema on the scalp?

Treatment of Scalp Eczema

Start with topical corticosteroids applied no more than twice daily to the affected scalp areas, using the least potent preparation that adequately controls symptoms. 1, 2

First-Line Treatment Approach

Topical Corticosteroids

• Apply betamethasone valerate lotion or similar corticosteroid formulations to the scalp twice daily (morning and night), massaging lightly until absorbed. 2
• Use the least potent preparation required to maintain control - this is the fundamental principle of eczema management. 3, 1
• Potent and very potent corticosteroids should be reserved for limited periods only, with implementation of "steroid holidays" (short breaks) when possible to minimize side effects. 3, 1
• Treatment should not be applied more than twice daily; many newer preparations are effective with once-daily application. 3
• Topical corticosteroids remain the therapeutic agent of choice for all scalp eczema presentations. 4

Essential Adjunctive Measures

• Liberal and regular application of emollients is the cornerstone of maintenance therapy, even when the eczema appears controlled. 1
• Apply emollients after bathing to provide a surface lipid film that retards water loss. 1
• Use soap-free cleansers and avoid alcohol-containing products on the scalp. 1
• Regular bathing for cleansing and hydrating the skin is recommended. 1

Managing Pruritus

• Sedating antihistamines (such as hydroxyzine or diphenhydramine) may help with nighttime itching through their sedative properties, not through direct anti-pruritic effects. 1
• Use sedating antihistamines at bedtime only; avoid daytime use. 3
• Large doses may be required in children. 3
• Non-sedating antihistamines have little to no value in atopic eczema and should not be used. 3, 1

Managing Secondary Infections

Bacterial Infections

• Watch for signs of secondary bacterial infection: increased crusting, weeping, or pustules. 1
• Flucloxacillin is the first-line oral antibiotic for Staphylococcus aureus, the most common pathogen in infected eczema. 3, 1
• Erythromycin should be used in patients with penicillin allergy or flucloxacillin resistance. 3
• Phenoxymethylpenicillin is indicated if β-hemolytic streptococci are isolated. 3
• Continue topical corticosteroids during bacterial infection when appropriate systemic antibiotics are given concurrently - do not withhold anti-inflammatory treatment. 1

Viral Infections (Eczema Herpeticum)

• If you observe grouped vesicles, punched-out erosions, or sudden deterioration with fever, suspect eczema herpeticum - this is a medical emergency. 1, 5
• Initiate oral acyclovir early in the disease course. 3, 1, 5
• In ill, feverish patients, administer acyclovir intravenously immediately. 3, 1, 5

Alternative Topical Agents

Tar Preparations

• Ichthammol (1% in zinc ointment) is less irritant than coal tar and may be particularly useful for healing lichenified eczema. 3
• Coal tar solution (1% strength) is generally preferred to crude coal tar. 3
• These agents do not cause systemic side effects related to percutaneous absorption unless used extravagantly. 3

Newer Anti-Inflammatory Options

• Recent network meta-analysis evidence shows potent topical corticosteroids, JAK inhibitors (ruxolitinib 1.5%), and tacrolimus 0.1% rank amongst the most effective treatments for eczema. 6
• PDE-4 inhibitors (crisaborole 2%, roflumilast 0.15%) rank amongst the least effective treatments. 6
• Tacrolimus 0.1% and pimecrolimus 1% are more likely to cause application-site reactions compared to corticosteroids. 6

Critical Safety Considerations

Corticosteroid-Related Concerns

• The main risk with topical corticosteroids is pituitary-adrenal axis suppression, particularly with prolonged use of potent preparations over large surface areas. 3, 2
• Short-term use (median 3 weeks, range 1-16 weeks) of mild to very potent topical corticosteroids shows no evidence for increased skin thinning. 6
• Longer-term use (6-60 months) does show increased skin thinning with mild to potent corticosteroids. 6
• Patients' or parents' fears of steroids often lead to undertreatment - explain the different potencies and the benefits/risks clearly to ensure compliance. 3, 1

Application Precautions

• Avoid occlusive dressings unless specifically directed, as they enhance systemic absorption. 2
• Pediatric patients may absorb proportionally larger amounts and are more susceptible to systemic toxicity. 2
• If irritation develops, discontinue topical corticosteroids and institute appropriate therapy. 2

When to Refer or Escalate

• Failure to respond to first-line management with moderate potency topical corticosteroids after 4 weeks is an indication for referral to a hospital specialist. 3, 1
• Need for systemic therapy or phototherapy requires specialist evaluation. 1
• Suspected eczema herpeticum requires immediate emergency treatment. 1, 5
• Systemic corticosteroids have a limited but definite role only for tiding occasional patients with severe atopic eczema through acute crises, after all other treatment avenues have been explored. 3, 1
• Systemic corticosteroids should never be used for maintenance treatment. 3, 1

Common Pitfalls to Avoid

• Do not delay or withhold topical corticosteroids when infection is present - they remain the primary treatment when appropriate systemic antibiotics are given concurrently. 1
• Do not use topical corticosteroids continuously without implementing "steroid holidays" when possible. 1
• Do not use systemic corticosteroids for chronic maintenance - they should only "tide over" acute severe flares. 7
• Ensure patients understand that treatment requires consistent, long-term application even when symptoms improve. 8