What is used to treat poison ivy?

Treatment of Poison Ivy Dermatitis

For mild to moderate poison ivy dermatitis, apply prescription-strength topical corticosteroids (mometasone furoate 0.1% ointment or betamethasone valerate 0.1% ointment) twice daily to affected areas, and for severe cases involving >30% body surface area or limiting self-care, initiate systemic prednisone 0.5-1 mg/kg daily for 7 days followed by a 4-6 week taper. 1, 2

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, 2
• Over-the-counter hydrocortisone preparations have NOT been shown to improve symptoms in randomized trials, despite FDA approval for poison ivy 2, 3
• 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 night for their sedative properties 1, 2
• Note that antihistamines may primarily help with sleep rather than directly relieving local itching 2

Moderate Cases with Persistent Pruritus

• Continue topical moderate-to-high potency corticosteroids twice daily 1
• If antihistamines fail to control pruritus, consider GABA agonists as second-line therapy: pregabalin 25-150 mg daily or gabapentin 900-3600 mg daily 1

Severe Cases

• 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 1, 2
• Continue high-potency topical corticosteroids to affected areas 1, 2
• Add oral antihistamines for symptomatic relief 1, 2
• Critical: Ensure the corticosteroid taper is long enough (4-6 weeks) to prevent rebound flare, which is a common pitfall 1, 2
• Systemic corticosteroids are necessary when >30% body surface area is involved or self-care is limited 1

Immediate Post-Exposure Decontamination

• Wash with soap and water immediately after contact: 100% removal if done immediately, 50% at 10 minutes, 25% at 15 minutes, and only 10% at 30 minutes 1, 2
• Remove contaminated clothing, jewelry, and brush off dry plant material before washing 2
• Commercial decontamination products or hand cleaners used within 2 hours can reduce symptoms by 55-70% 1, 2

Supportive Care Measures

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

Critical Warning Signs Requiring Antibiotic Therapy

• Check for secondary bacterial infection: increased warmth, tenderness, purulent drainage, honey-colored crusting, or cellulitis all require antibiotic therapy 1, 2

Common Pitfalls to Avoid

• Do not rely on over-the-counter hydrocortisone—it lacks evidence of efficacy in randomized trials 2
• Do not use short corticosteroid tapers (<4 weeks), as this leads to rebound flare 1, 2
• Do not delay systemic corticosteroids in severe cases, as prescription-strength topical corticosteroids combined with systemic steroids have demonstrated efficacy in reducing itch duration 2