High-dose vitamin C therapy for inclusion body myositis.

OBJECTIVES: The efficiency of high-dose vitamin C therapy for inclusion body myositis (IBM) was assessed. SUBJECTS & METHODS: The subjects were five patients with IBM confirmed pathologically. After the intravenous administration of 40 mg/kg vitamin C five times/week for four weeks, muscle weakness was found to improve in three cases. The average muscle score improved from 8.1 to 8.8, from 7.0 to 8.1 and from 6.2 to 6.8. Magnetic resonance imaging (MRI) demonstrated a reduction in the size of T2 high lesions and gadolinium enhancement in the thigh muscles in one case. Based on our findings, high-dose vitamin C therapy is considered to be effective in some cases of IBM.