What is the treatment for poison ivy (Toxicodendron radicans) rash?

Treatment of Poison Ivy Rash

Immediate washing with soap and water or a commercial decontamination product is the most effective first-line treatment for poison ivy exposure, with effectiveness decreasing significantly after 30 minutes of contact. 1

Immediate Management

• Wash the exposed area with soap and water or a commercial decontamination product as soon as possible after exposure to remove urushiol oil (the allergic compound in poison ivy) 1
• Effectiveness of washing decreases with time: 100% effective immediately, 50% at 10 minutes, 25% at 15 minutes, and only 10% at 30 minutes 1
• Commercial decontamination products, hand cleaners, or dishwashing soap with water can reduce symptoms by 55-70% even when used up to 2 hours after exposure 1

Symptomatic Treatment Options

Recommended Treatments:

• Cool compresses may provide relief for local symptoms and itching 1
• Oatmeal baths can help soothe itching and are frequently recommended for symptomatic relief 1
• Prescription-strength topical corticosteroids may be beneficial, though over-the-counter options have limited evidence of effectiveness 1
• Systemic corticosteroids combined with high-potency topical corticosteroids may reduce the duration of itching in severe cases 1

Treatments with Limited Evidence:

• Over-the-counter topical steroids (0.2-2.5% hydrocortisone preparations) have not been shown to significantly improve symptoms in controlled studies 1
• Over-the-counter oral antihistamines have uncertain effectiveness for itching relief but may help with sleep at night 1
  • One observational study with 89 participants did not find statistically significant symptom reduction with oral antihistamines 1

Clinical Considerations

• Poison ivy dermatitis is a self-limiting condition that typically resolves within 2-3 weeks 2, 3
• The rash presents with redness, papules, vesicles, and intense itching, usually starting within days of exposure 1
• Severity of symptoms correlates with the area exposed and duration of contact 1
• Approximately 50-75% of individuals are allergic to urushiol, the compound in poison ivy 1

Special Situations

• For severe cases with extensive rash or involvement of face, genitals, or large body surface area, consider:
  • Physician consultation 2
  • Systemic corticosteroids 3
• Hydrocortisone is FDA-approved for temporarily relieving itching associated with poison ivy, oak, and sumac 4

Prevention Tips

• Recognize and avoid the plant (three leaflets per leaf) 5
• Wear protective clothing when in areas where poison ivy may be present 6
• If exposure occurs, washing with dishwashing soap, commercial hand cleaner (Goop), or specialized products (Tecnu) all provide significant protection (56-70%) compared to no treatment 7