Poison Oak Dermatitis Treatment Guidelines
Treat poison oak dermatitis based on body surface area involvement: use high-potency topical corticosteroids alone for mild cases (<10% BSA), and add systemic corticosteroids for severe cases (>30% BSA or symptoms limiting self-care), with systemic steroids prescribed for at least 14 days to prevent treatment failure. 1, 2
Severity Assessment and Classification
Before initiating treatment, quantify the extent of involvement to guide therapy intensity 1, 3:
- Mild (Grade 1): <10% body surface area involvement with minimal symptoms 3
- Moderate (Grade 2): 10-30% BSA involvement or significant symptoms limiting instrumental activities of daily living 3
- Severe (Grade 3): >30% BSA involvement or severe symptoms limiting self-care 3
Examine for signs of secondary bacterial infection including increased warmth, tenderness, purulent drainage, honey-colored crusting, or surrounding cellulitis, as this requires antibiotic therapy in addition to corticosteroids 1, 3
Treatment Algorithm by Severity
Mild Disease (<10% BSA)
Apply high-potency topical corticosteroid (such as clobetasol propionate 0.05%) twice daily to all affected areas. 1
- Topical corticosteroids alone suffice for mild cases 1
- Hydrocortisone is FDA-approved for temporary relief of itching associated with poison ivy and oak dermatitis 4
- Continue treatment until lesions resolve 1
Moderate to Severe Disease (>10% BSA or limiting symptoms)
Initiate systemic corticosteroids in addition to topical therapy for cases involving more than 30% BSA or symptoms limiting self-care. 1
- Prescribe systemic corticosteroids for a minimum of 14-20 days, not the commonly used shorter courses. 2
- Shorter duration oral corticosteroids (1-13 days) significantly increase the risk of return visits (OR 1.30,95% CI 1.17-1.44, p<0.001) 2
- Continue high-potency topical corticosteroids twice daily to affected areas concurrently 1
Critical Pitfalls to Avoid
The most common treatment error is prescribing systemic corticosteroids for insufficient duration. 2
- 86% of prescriptions in emergency settings are for only 1-13 days, leading to increased healthcare utilization for undertreated disease 2
- Worsening symptoms after two weeks suggests continued allergen exposure or inadequate treatment 1, 3
- Document the percentage of BSA involvement in the medical record to justify treatment intensity 1
- Always check for secondary infection before initiating corticosteroid therapy, as steroids alone will worsen bacterial superinfection 1
Special Considerations
Patients initially treated in emergency departments have higher return visit rates compared to those treated by primary care or dermatology (OR 0.87 and 0.89 respectively), likely reflecting more severe disease presentation 2
When severe disease presents to acute care settings, prescribe 2-3 weeks of systemic steroids when no contraindications exist 2