What is the treatment for poison ivy?

Treatment of Poison Ivy Dermatitis

For mild to moderate poison ivy, apply prescription-strength topical corticosteroids (mometasone furoate 0.1% or betamethasone valerate 0.1% ointment) twice daily and add oral antihistamines for itch control; for severe cases or involvement of >30% body surface area, immediately initiate systemic prednisone 0.5-1 mg/kg daily for 7 days followed by a 4-6 week taper to prevent rebound flare. 1

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 1
• Over-the-counter hydrocortisone preparations have not demonstrated efficacy in randomized trials, though FDA-approved for temporary relief of itching 1, 2
• Add oral antihistamines for pruritus control: use 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 bedtime for sedative properties 1
• If antihistamines fail, consider GABA agonists as second-line therapy: pregabalin 25-150 mg daily or gabapentin 900-3600 mg daily 1

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

• Initiate systemic corticosteroids immediately: prednisone 0.5-1 mg/kg body weight for 7 days 1
• Critical: Follow with a weaning dose over 4-6 weeks to prevent rebound flare—this is the most common pitfall in management 1
• Continue topical corticosteroids to affected areas and add oral antihistamines for symptomatic relief 1
• Systemic steroids combined with prescription-strength topical corticosteroids have demonstrated efficacy in reducing itch duration 1

Supportive Care Measures

• Apply cool compresses for symptomatic relief 1
• Use oatmeal baths for widespread pruritus 1
• Apply alcohol-free moisturizing creams or ointments twice daily, preferably with urea-containing (5%-10%) moisturizers 1
• Avoid frequent washing with hot water and avoid skin irritants including over-the-counter anti-acne medications, solvents, or disinfectants 1
• Apply sunscreen SPF 15 to exposed areas every 2 hours when outside 1

Post-Exposure Decontamination (If Caught Early)

• Washing with soap and water removes urushiol: 100% removal if done immediately, 50% at 10 minutes, 25% at 15 minutes, and only 10% at 30 minutes 1
• Commercial decontamination products or hand cleaners used within 2 hours can reduce symptoms by 55-70% 1
• In one study, surfactant soap (Dial), oil-removing compound (Goop), and chemical inactivation (Tecnu) showed 56.4%, 61.8%, and 70% protection respectively when applied after exposure 3

Critical Pitfalls to Avoid

• Ensure systemic corticosteroid tapers are long enough (4-6 weeks) to prevent rebound flare—inadequate taper duration is a common cause of treatment failure 1
• Monitor for secondary bacterial infection: check for increased warmth, tenderness, purulent drainage, honey-colored crusting, or cellulitis, which require antibiotic therapy 1
• Recognize that systemic corticosteroids are necessary when >30% body surface area is involved or self-care is limited 1
• The dermatitis is self-limiting and typically resolves within 2-3 weeks, but continued exposure to urushiol prolongs the reaction 4, 5