Adults

Dosage varies widely based on condition and severity, typically 10-250 mg IV/IM, up to 1 gm daily for severe cases (e.g., MS exacerbations, organ transplant rejection). High doses are usually administered for short periods.

Elderly

No specific dose adjustment is usually needed, but close monitoring for adverse effects is recommended due to potential comorbidities.

Renal_impairment

No specific dose adjustment is generally needed for renal impairment, but caution is advised in fluid retention cases.

Onset

Varies by condition and route of administration; intravenous effects usually begin within minutes to hours.

Excretion

Mainly excreted in the urine as inactive metabolites.

Half life

Plasma half-life is approximately 2.5 to 3.5 hours, but the biological half-life (duration of action) is much longer (18-36 hours).

Absorption

Rapidly absorbed after intramuscular or intravenous administration. Peak plasma concentrations are typically reached within 1 hour.

Metabolism

Primarily metabolized in the liver by the cytochrome P450 3A4 (CYP3A4) enzyme system.

Anticoagulants (e.g., warfarin)

Corticosteroids may potentiate or inhibit the effects of anticoagulants; close monitoring of INR is required.

NSAIDs (Nonsteroidal Anti-inflammatory Drugs)

Concomitant use may increase the risk of gastrointestinal ulceration and bleeding.

CYP3A4 Inducers (e.g., phenobarbital, rifampicin)

May decrease methylprednisolone plasma levels, requiring dose adjustment.

CYP3A4 Inhibitors (e.g., ketoconazole, erythromycin)

May increase methylprednisolone plasma levels, potentially leading to increased adverse effects.