What is the role of the Goeckerman regimen in treating psoriatic arthritis?

The Role of Goeckerman Regimen in Psoriatic Arthritis

The Goeckerman regimen is not specifically recommended in current treatment guidelines for psoriatic arthritis, as it primarily targets the skin manifestations of psoriasis rather than the joint inflammation characteristic of psoriatic arthritis.

Understanding Psoriatic Arthritis Treatment Approach

Psoriatic arthritis (PsA) is a heterogeneous inflammatory disease requiring targeted treatment of both musculoskeletal and skin manifestations. Current treatment guidelines from EULAR (2019) and ACR/NPF (2018) focus on pharmacologic therapies that address the underlying inflammatory process affecting both joints and skin.

First-line Treatments for PsA

According to treatment guidelines:

• For peripheral arthritis, conventional synthetic DMARDs (csDMARDs) should be initiated rapidly 1

  • Methotrexate is preferred in patients with significant skin involvement 1
  • NSAIDs may be used for symptomatic relief of musculoskeletal symptoms 1
  • Local glucocorticoid injections can be considered as adjunctive therapy 1

• For inadequate response to csDMARDs:

  • Biological DMARDs (bDMARDs) are recommended, with IL-17 or IL-12/23 inhibitors preferred when there is significant skin involvement 1
  • JAK inhibitors may be considered after inadequate response to csDMARDs and bDMARDs 1

Goeckerman Therapy: Limited Role in PsA

The Goeckerman regimen combines ultraviolet B (UVB) light exposure with application of crude coal tar and has been established as a treatment for moderate to severe psoriasis skin lesions 2. However:

• It is not mentioned in current PsA treatment guidelines from EULAR or ACR/NPF 1
• It primarily targets skin manifestations rather than joint inflammation
• The therapy requires specialized expertise and is available at limited centers 2
• Studies evaluating Goeckerman therapy have focused on skin psoriasis outcomes rather than joint symptoms 3, 4, 5

Efficacy for Skin Manifestations

While not specifically indicated for PsA, Goeckerman therapy has shown effectiveness for treatment-resistant psoriasis:

• It can produce dramatic improvement in severe generalized plaque-type psoriasis within 28 days 4
• Modified Goeckerman therapy (crude coal tar 2.5% plus UVA) demonstrated significant reduction in PASI scores, with 63.6% of patients achieving >50% reduction 5
• The therapy combines UVB light with coal tar application, though some studies question whether the tar component adds significant benefit beyond the UVB alone 6, 7

Clinical Considerations

For patients with PsA who have severe skin manifestations that are resistant to conventional therapies:

1. Primary treatment should focus on systemic therapies that address both joint and skin manifestations (csDMARDs, bDMARDs, or JAK inhibitors) 1

2. Goeckerman therapy could be considered as an adjunctive treatment specifically for resistant skin manifestations, particularly when:

   • Skin disease is severe and treatment-resistant
   • The patient has access to specialized centers that offer this therapy 2
   • The patient has no contraindications to phototherapy

3. Important limitations to consider:

   • Requires expertise in both coal tar application and phototherapy administration 2
   • Time-intensive treatment requiring frequent visits
   • Limited availability at specialized centers
   • Potential side effects including phototoxicity, folliculitis, and contact dermatitis 2

Conclusion

While Goeckerman therapy may be effective for treating the skin manifestations of psoriasis, it is not specifically recommended in current treatment guidelines for psoriatic arthritis. The primary approach to PsA should focus on systemic therapies that address both joint and skin inflammation, with Goeckerman therapy potentially considered as an adjunctive treatment for severe, treatment-resistant skin manifestations in selected patients who have access to centers offering this specialized therapy.