What is the most effective treatment, salicylic acid or urea, and formulation for a patient with mild eczema and obsessive-compulsive disorder experiencing dryness on the feet?

Treatment Recommendation for Mild Foot Eczema with Dryness in OCD

For mild eczema with dryness on the feet in a patient with OCD, use a urea-based cream (not lotion or ointment) at 5-10% concentration applied twice daily, as this formulation provides optimal adherence for patients with compulsive behaviors while effectively treating both the dryness and mild inflammation.

Why Urea Over Salicylic Acid

• Urea is specifically recommended for eczematous dry skin and addresses both the xerosis and inflammatory component of mild eczema 1
• Urea-containing moisturizers are the guideline-recommended first-line treatment for dry skin conditions, with concentrations of 5-10% appropriate for general dry skin and pruritus relief 2, 3
• Urea has anti-inflammatory properties through regulation of epidermal gene expression and keratinocyte differentiation, making it superior for eczema versus pure keratolytics like salicylic acid 4
• Salicylic acid is not mentioned in any guideline recommendations for eczematous conditions and lacks the moisturizing and barrier-enhancing properties essential for eczema management 5, 4

Optimal Formulation: Cream

Creams are the best choice for patients with OCD for several critical reasons:

• Oil-in-water creams are specifically preferred over alcohol-containing lotions or gels for eczema and xerotic skin 1
• Creams provide a middle ground between lotions (too thin, requiring frequent reapplication that may trigger compulsive behaviors) and ointments (too greasy, potentially triggering contamination fears or texture aversions common in OCD)
• The British Association of Dermatologists recommends 10% urea cream applied twice daily as the standard regimen for dry skin and pruritus 3
• Creams are well-tolerated and effective for non-inflamed dry skin conditions 6

Application Protocol

• Apply 5-10% urea cream twice daily to affected foot areas 3, 7
• Apply after bathing when skin is slightly damp to optimize absorption and lock in moisture 2, 3
• For mild inflammatory lesions (the eczema component), consider adding topical hydrocortisone cream as needed 1
• Avoid alcohol-containing solutions and harsh soaps 1

OCD-Specific Considerations

• A twice-daily fixed schedule provides structure that can work with rather than against compulsive tendencies, reducing anxiety about "when" and "how much" to apply
• Creams have a defined endpoint of absorption (they disappear into skin), which may reduce compulsive reapplication behaviors compared to ointments that remain visible
• The non-greasy nature of creams reduces contamination concerns that might trigger avoidance or excessive washing 3

Safety Profile

• Urea 5-10% is well-tolerated with minimal side effects 7, 8
• The most common adverse effect is mild smarting or stinging, which occurs less frequently with urea compared to other keratolytics 7
• Avoid application to open fissures or actively inflamed/broken skin, as this may cause burning sensations 3, 6
• No systemic toxicity has been reported with topical urea use 8

Reassessment

• Evaluate response after 2 weeks of consistent use 1
• If no improvement, consider increasing urea concentration to 10-20% or adding topical corticosteroids for the inflammatory component 3
• If worsening occurs, reassess for secondary infection or contact dermatitis 1