Many clinicians use IV pulse GCs as the initial treatment of severe life-threatening or organ-threatening presentations of rheumatic diseases. This is typically methylprednisolone given in doses of 1 g/day for 3 to 5 consecutive days. Many physicians split the dose (500 mg IV q12 hours or 250 mg IV q6 hours) on inpatients to lessen potential side effects. This regimen of GC administration is considered to have more immunomodulating effects than high-dose daily oral GCs through rapid (within minutes) nongenomic mechanisms including cell membrane physiochemical effects (controversial). As the sole therapeutic intervention, pulse steroids probably have no role in long-term therapy. However, in combination therapy with a cytotoxic agent, pulse steroids may provide time for a second agent to achieve its therapeutic effect.
The effect of pulse steroids usually lasts 4 to 6 weeks with wide variation between patients. It has been used most often in the treatment of severe vasculitis, lupus nephritis, and neuropsychiatric lupus. Side effects include psychosis, arrhythmias (some from hypokalemia), glucose intolerance, hypertension, glaucoma, and, rarely, sudden death. The risk of these adverse effects may be lessened by using a slow rate of infusion and ensuring that the serum potassium level is normal.