What is the oral (PO) steroid dosage for recurrent poison ivy rash?

Oral Steroid Dosing for Recurrent Poison Ivy Rash

For recurrent poison ivy rash, prednisone should be prescribed at 0.5-1 mg/kg/day for a total course of 14-21 days to prevent return of symptoms and reduce healthcare utilization. 1, 2

Recommended Dosing Regimen

Severe Poison Ivy Dermatitis

• Initial dose: Prednisone 0.5-1 mg/kg/day (typically 40 mg daily for average adult)
• Duration: 14-21 days total course
• Tapering schedule:
  • Days 1-5: 40 mg daily
  • Days 6-7: 30 mg daily
  • Days 8-9: 20 mg daily
  • Days 10-11: 10 mg daily
  • Days 12-15: 5 mg daily

Rationale for Extended Course

• Shorter courses (less than 14 days) are associated with significantly higher rates of symptom return and increased use of additional medications 3, 2
• Patients receiving longer courses are significantly less likely to utilize other medications (22.7% vs. 55.6%) 3
• Number needed to treat is approximately 3 for preventing use of additional medications 3

Considerations for Specific Situations

Moderate Disease (10-30% BSA)

• Consider starting with the same dosing but may use shorter duration (10-14 days)
• Always include a proper taper to prevent rebound dermatitis

Extensive Disease (>30% BSA)

• Use the full recommended dose and duration
• May require higher initial dosing (up to 1 mg/kg/day) 1
• Consider adjunctive treatments (topical steroids, antihistamines)

Monitoring and Follow-up

• Evaluate response within 5-7 days
• If symptoms worsen or don't improve, reassess diagnosis and consider dermatology referral
• Monitor for steroid side effects, especially in patients with diabetes, hypertension, or peptic ulcer disease 1

Common Pitfalls to Avoid

1. Insufficient duration: Emergency clinicians often prescribe courses that are too short (1-13 days), leading to return visits 2
2. Inadequate initial dosing: Starting with too low a dose may result in inadequate control of inflammation
3. Abrupt discontinuation: Failing to taper can lead to rebound dermatitis
4. Overlooking contraindications: Always consider patient's medical history before prescribing systemic steroids 1

Adjunctive Treatments

• Topical high-potency steroids (clobetasol 0.05% or betamethasone 0.05%) twice daily for up to 2 weeks for localized areas 1
• Oral antihistamines for pruritus (cetirizine/loratadine 10 mg daily or hydroxyzine 10-25 mg four times daily) 1
• Cool compresses and oatmeal baths for symptomatic relief 1

The evidence strongly supports longer courses (14-21 days) of oral prednisone for recurrent or severe poison ivy dermatitis to prevent symptom return and reduce healthcare utilization 3, 2.