How to switch a patient from hydrocortisone 50mg (intravenous) every 6 hours back to their home dose of dexamethasone (Decadron) 2mg daily?

Switching from IV Hydrocortisone to Oral Dexamethasone

To switch from hydrocortisone 50mg IV every 6 hours back to home dose dexamethasone 2mg daily, taper the hydrocortisone over 24-48 hours while restarting the dexamethasone, rather than abruptly discontinuing the IV medication. 1, 2

Conversion Strategy

1. Day 1:

   • Continue hydrocortisone 50mg IV every 6 hours in the morning
   • Start dexamethasone 2mg PO with the morning dose
   • Reduce hydrocortisone to 50mg IV every 8 hours for remainder of day

2. Day 2:

   • Continue dexamethasone 2mg PO in the morning
   • Reduce hydrocortisone to 50mg IV every 12 hours

3. Day 3:

   • Continue dexamethasone 2mg PO daily
   • Discontinue hydrocortisone completely

Rationale for Tapering

• Abrupt discontinuation of high-dose corticosteroids can lead to adrenal insufficiency symptoms and potential adrenal crisis 2, 3
• The patient was receiving approximately 200mg of hydrocortisone daily (equivalent to about 8mg of dexamethasone), so tapering is necessary to avoid withdrawal symptoms 2, 4
• Dexamethasone has approximately 25 times the glucocorticoid potency of hydrocortisone 4, making the 2mg daily dose roughly equivalent to 50mg of hydrocortisone

Monitoring During Transition

• Monitor for signs of adrenal insufficiency during the transition: hypotension, fatigue, nausea, vomiting, weakness, or electrolyte abnormalities 2
• Check morning cortisol levels if symptoms of adrenal insufficiency develop 2
• Monitor blood glucose levels during the transition as hyperglycemia is a common side effect of corticosteroid therapy 1

Important Considerations

• If the patient has been on high-dose IV hydrocortisone for more than 1-2 weeks, a more gradual taper might be necessary 3
• If the patient shows signs of adrenal insufficiency during the taper (hypotension, fatigue, nausea), slow the taper by extending each step to 48 hours 2
• Ensure the patient understands the importance of not missing doses of dexamethasone to prevent adrenal crisis 2

Special Circumstances

• If the patient is unable to take oral medications, consider using dexamethasone IV at equivalent doses until oral intake is possible 5
• If the patient is experiencing acute illness or stress during the transition, maintain higher steroid doses until the stressor resolves 1, 2

This approach balances the need to return to the patient's home regimen while preventing symptoms of adrenal insufficiency that could occur with abrupt discontinuation of high-dose steroids.