What is the treatment for poison ivy?

Treatment of Poison Ivy Dermatitis

Immediately wash the exposed area with soap and water, commercial hand cleaners, or dishwashing soap—this removes 100% of urushiol if done instantly but drops to only 10% effectiveness at 30 minutes, making speed critical. 1, 2

Immediate Decontamination (Time-Sensitive)

• Remove all contaminated clothing, jewelry, and materials from the exposure area first, then brush off any dry plant material before washing 1
• Washing effectiveness decreases rapidly: 50% removal at 10 minutes, 25% at 15 minutes, and only 10% at 30 minutes after exposure 1, 2
• Commercial decontamination products or hand cleaners can still reduce symptoms by 55-70% even when used up to 2 hours after exposure 1, 2, 3
• Standard dishwashing soap (like Dial) provides 56.4% protection and costs only $0.07 per ounce compared to commercial products at $1.25 per ounce, with no statistically significant difference in effectiveness 3

Treatment Algorithm by Severity

Mild to Moderate Cases

Apply moderate-to-high potency topical corticosteroids (mometasone furoate 0.1% ointment or betamethasone valerate 0.1% ointment) twice daily to affected areas 2

• Over-the-counter hydrocortisone preparations have NOT been shown to improve symptoms in randomized trials and should not be relied upon 2
• Add cool compresses to affected areas for symptomatic relief 1, 2
• Consider oatmeal baths for widespread pruritus 1, 2
• Use oral antihistamines: non-sedating second-generation antihistamines (loratadine 10 mg daily) during daytime, or first-generation antihistamines (diphenhydramine 25-50 mg or hydroxyzine 25-50 mg) at night for sedation and itch relief 2
• If antihistamines fail, consider GABA agonists as second-line therapy: pregabalin 25-150 mg daily or gabapentin 900-3600 mg daily 2

Severe Cases (>30% Body Surface Area or Significant Functional Impairment)

Initiate systemic corticosteroids immediately with prednisone 0.5-1 mg/kg body weight for 7 days, followed by a weaning dose over 4-6 weeks 2

• Continue topical moderate-to-high potency corticosteroids to affected areas twice daily 2
• Add oral antihistamines for additional symptom control 2
• The combination of systemic and high-potency topical corticosteroids has been shown to reduce the duration of itching 1, 2

Supportive Care Measures

• Apply alcohol-free moisturizing creams or ointments twice daily, preferably with urea-containing (5%-10%) moisturizers 2
• Avoid frequent washing with hot water, which can worsen symptoms 2
• Avoid skin irritants including over-the-counter anti-acne medications, solvents, or disinfectants 2
• Apply sunscreen SPF 15 to exposed areas every 2 hours when outside 2

Critical Pitfalls to Avoid

• Ensure systemic corticosteroid tapers are long enough (4-6 weeks minimum) to prevent rebound flare—short courses commonly lead to recurrence 2
• Do not delay washing after exposure; every minute counts in preventing dermatitis development 1, 2
• Do not rely solely on over-the-counter hydrocortisone for anything beyond the mildest cases 2
• Monitor for secondary bacterial infection: increased warmth, tenderness, purulent drainage, honey-colored crusting, or cellulitis require antibiotic therapy 2
• Systemic corticosteroids are necessary when >30% body surface area is involved or when self-care is limited 2
• Unless treating hands, wash hands thoroughly with soap and water immediately after applying any topical treatment to prevent inadvertent spread to eyes or mucous membranes 4