Why are oral corticosteroids avoided in the treatment of psoriasis?

Why Oral Corticosteroids Are Avoided in Psoriasis

Oral corticosteroids are contraindicated in psoriasis because stopping or reducing their dose can precipitate life-threatening complications including erythrodermic psoriasis, generalized pustular psoriasis (von Zumbusch type), or severe unstable psoriasis with widespread skin involvement. 1, 2, 3

Primary Mechanism of Harm

The fundamental problem with systemic corticosteroids in psoriasis is the rebound phenomenon that occurs during tapering or withdrawal:

• Withdrawal triggers severe disease flares characterized by rapidly progressing erythematous plaques that can evolve into erythrodermic psoriasis with widespread skin involvement 2
• Generalized pustular psoriasis may develop with sterile pustules, fever, hypotension, general weakness, and risk of metabolic complications that can be life-threatening 2
• These complications represent a qualitative worsening of disease, not just a return to baseline severity 1, 3

Limited Exceptions (Rare Circumstances Only)

The British Medical Journal guidelines specify only three narrow indications where systemic corticosteroids may be considered 1:

1. Persistent uncontrollable erythroderma causing metabolic complications
2. Generalized pustular psoriasis of von Zumbusch type when other drugs are contraindicated
3. Hyperacute psoriatic polyarthritis threatening severe irreversible joint damage

Even in these scenarios, corticosteroids should be used with extreme caution and only as a bridge to definitive therapy. 1

Evidence Quality Considerations

There is a notable discrepancy between clinical practice and guidelines 4:

• Real-world data shows systemic steroids are widely prescribed for psoriasis (up to 30% of patients in some registries) 1
• However, lack of clinical trial evidence supporting efficacy combined with well-documented case reports of severe adverse outcomes justify the strong contraindication 1, 4
• The 2013 literature review found a "remarkable lack" of systematic data given widespread use, but the potential for catastrophic outcomes (erythrodermic/pustular transformation) outweighs any theoretical benefit 4

Practical Management Algorithm

If a patient is currently on oral corticosteroids for psoriasis:

1. Immediately initiate controlled tapering over several weeks while monitoring closely for disease worsening 3
2. Simultaneously start appropriate psoriasis-specific therapy before completing the taper 3:
   • For mild-moderate disease: Medium-to-high potency topical corticosteroids with vitamin D analogs 3
   • For moderate-severe disease: Acitretin, methotrexate, or cyclosporine 3
   • For severe/unstable disease: Infliximab 5 mg/kg IV at weeks 0,2, and 6 as the preferred rapid-acting biologic 2
3. Monitor weekly during taper using body surface area or PASI scoring 3

Contrast with Psoriatic Arthritis

In psoriatic arthritis, the evidence is more nuanced 1, 5:

• Low-dose systemic corticosteroids (≤7.5 mg/day) are used in up to 30% of patients, though without clinical trial evidence 1
• The American College of Rheumatology still recommends avoiding oral corticosteroids as monotherapy due to lack of efficacy data and psoriasis flare risk 5
• Intra-articular injections are acceptable for persistently inflamed joints if avoiding injection through psoriatic plaques 1, 5

Critical Caveat

The risk of severe rebound is highest in patients with:

• Extensive skin involvement at baseline 1
• Rapid corticosteroid withdrawal rather than gradual taper 3
• No concomitant DMARD or psoriasis-specific therapy 1

Patient education is essential: Explain that systemic corticosteroids can transform stable plaque psoriasis into life-threatening erythrodermic or pustular variants, emphasizing the need for appropriate long-term psoriasis management rather than short-term symptom suppression. 3