Methylprednisolone to Prednisone Conversion
16 mg of methylprednisolone is equivalent to 20 mg of prednisone.
Conversion Ratio
The standard conversion between these corticosteroids is based on their relative potencies:
- Methylprednisolone is 5 times more potent than hydrocortisone 1
- Prednisone is 4 times more potent than hydrocortisone 1
- Therefore, 4 mg of methylprednisolone equals 5 mg of prednisone 2
Using this ratio: 16 mg methylprednisolone × (5/4) = 20 mg prednisone
Clinical Context for Conversion
This conversion is critical when:
- Switching between oral formulations due to availability, cost, or patient preference 2
- Transitioning from IV methylprednisolone to oral prednisone after initial treatment 3
- Calculating cumulative steroid exposure to assess HPA axis suppression risk 4, 5
Important Dosing Considerations
Bioavailability Differences
- Oral prednisone and methylprednisolone have comparable bioavailability when given in equivalent doses 3, 6
- No dose adjustment is needed beyond the 4:5 conversion ratio for routine oral-to-oral switches 6
Timing Between Courses
If you recently completed a methylprednisolone course and are considering starting prednisone:
- Wait at least 1-2 weeks after completing a standard 6-day taper before starting another corticosteroid course 5
- Extend to 3-4 weeks if you have diabetes, hypertension, osteoporosis, or glaucoma due to higher risk of cumulative complications 5
Common Pitfall: Underdosing
The standard methylprednisolone dose pack (4 mg tablets, 6-day taper) provides only 84 mg total methylprednisolone, equivalent to approximately 105 mg prednisone over 6 days 1, 4. This is substantially less than therapeutic dosing for many inflammatory conditions, which typically requires prednisone 1 mg/kg/day (maximum 60 mg daily) for 10-14 days 1.
Practical Application
For your 16 mg methylprednisolone dose: