What is the treatment for Cushing's syndrome induced by exogenous (external) steroids?

Treatment for Exogenous Steroid-Induced Cushing's Syndrome

The primary treatment for exogenous steroid-induced Cushing's syndrome is gradual tapering and discontinuation of the causative steroid medication, while preventing adrenal insufficiency through careful monitoring and appropriate replacement therapy. 1

Initial Management

• Identify and discontinue the source of exogenous steroids when clinically feasible, whether it's oral, injectable, topical, or inhaled corticosteroids 2, 3
• Never abruptly withdraw steroid therapy as this can lead to adrenal insufficiency due to hypothalamic-pituitary-adrenal (HPA) axis suppression 1
• Implement a gradual tapering schedule based on:
  • Duration of previous steroid therapy
  • Dose of steroid used
  • Individual patient response 1

Tapering Protocol

• For long-term steroid users (>3 weeks), reduce the dose by approximately 5-10% every 1-2 weeks 1
• Consider alternate-day therapy during tapering to help restore normal HPA axis function while maintaining therapeutic effect 1
• Morning administration (before 9 am) is preferred to minimize HPA axis suppression 1
• Monitor for signs of adrenal insufficiency during tapering, including fatigue, weakness, hypotension, nausea, vomiting, and hypoglycemia 1, 4

Management of Steroid Withdrawal Syndrome

• Steroid withdrawal syndrome may develop despite acceptable cortisol levels, presenting with symptoms similar to adrenal insufficiency 4
• Treatment involves temporary increase in glucocorticoid replacement dose with typical duration of 6-10 months 4
• Slower tapering regimen may reduce risk of withdrawal syndrome 4

Special Considerations

For Topical Steroid-Induced Cushing's

• Immediately discontinue or reduce potent topical steroids when Cushing's features are identified 2, 3
• Avoid occlusive dressings which increase systemic absorption 2
• Limit high-potency topical steroid use (e.g., clobetasol) to less than 50g per week 2

For Inhaled Steroid-Induced Cushing's

• Consider switching to lower-dose inhaled steroids or alternative medications for underlying condition 5
• Use spacer devices with inhaled steroids to reduce systemic absorption 5
• Rinse mouth after inhaled steroid use to decrease swallowed portion 5

Monitoring During Treatment

• Regular assessment of cortisol levels to evaluate HPA axis recovery 4
• Stress dose steroids during illness or surgery may be needed for up to 12 months after discontinuation of long-term steroid therapy 1
• Monitor for resolution of Cushing's features including weight, blood pressure, glucose levels, and physical stigmata 5

Adjunctive Treatments

• For hypertension, consider spironolactone or eplerenone 6
• For hyperglycemia, appropriate glucose-lowering therapy 6
• For hypokalemia, potassium supplementation 6
• For severe cases with complications, consider medications that block cortisol synthesis (ketoconazole, metyrapone) or action (mifepristone) while tapering the exogenous steroid 5, 7, 8

Pitfalls to Avoid

• Avoid abrupt steroid discontinuation which can precipitate adrenal crisis 1
• Don't underestimate recovery time - HPA axis may take 6-12 months to fully recover after long-term steroid use 1
• Don't forget stress dose steroids during acute illness, surgery, or other stressful events until HPA axis recovery is confirmed 1