Methylprednisolone 100 mg to Prednisone Equivalency
Methylprednisolone 100 mg is equivalent to 125 mg of prednisone, based on the established conversion ratio where 4 mg of methylprednisolone equals 5 mg of prednisone. 1
Conversion Ratio and Evidence
- The FDA-approved drug labeling for methylprednisolone clearly establishes that 4 mg of methylprednisolone is equivalent to 5 mg of prednisolone/prednisone 1
- Using this conversion ratio:
- 4 mg methylprednisolone = 5 mg prednisone
- Therefore, 100 mg methylprednisolone = 125 mg prednisone
Clinical Applications
- This conversion ratio is consistently applied in clinical practice guidelines, such as those for acute severe ulcerative colitis (ASUC), where 60 mg methylprednisolone daily is considered equivalent to higher doses of hydrocortisone 2
- When switching between these medications, maintaining equivalent anti-inflammatory potency is crucial for managing conditions requiring corticosteroid therapy 2
Pharmacological Considerations
- Methylprednisolone has less mineralocorticoid effect than hydrocortisone at equivalent anti-inflammatory doses, resulting in significantly less hypokalaemia 2
- The pharmacokinetic and pharmacodynamic properties of methylprednisolone differ from prednisone, which explains why the conversion is not 1:1 3
Clinical Implications
- When converting between corticosteroids, it's important to maintain equivalent anti-inflammatory potency to ensure continued therapeutic effect 3
- Studies comparing different corticosteroids have shown that maintaining appropriate dose equivalency is important for achieving similar clinical outcomes 4, 5
- The established conversion ratio has been validated through pharmacodynamic studies examining cell trafficking and cortisol dynamics 3
Common Pitfalls to Avoid
- Failing to adjust for the different potencies when switching between corticosteroids can lead to either under-treatment or increased side effects 1
- Some clinicians incorrectly use a 1:1 conversion, which would result in under-dosing when switching from methylprednisolone to prednisone 3
- When converting between IV and oral formulations, bioavailability differences must also be considered, though this doesn't affect the basic potency ratio 4
Remember that while 100 mg methylprednisolone equals 125 mg prednisone in terms of anti-inflammatory potency, individual patient responses may vary based on metabolism, comorbidities, and concurrent medications 1.