High-dose IV vitamin C: no excess harm vs placebo in RCTs, but real documented complications exist
High-dose intravenous vitamin C, a common ingredient in Myers'-Cocktail-style wellness IV formulas, shows no consistent excess harm compared with placebo across nine double-blind randomized controlled trials, but the wider literature of 74 studies documents real complications including oxalate nephropathy, hypernatremia, and hemolysis in patients with G6PD deficiency.
Safety notes
Screen for G6PD deficiency and renal impairment before high-dose IV vitamin C; monitor sodium and renal markers with repeated or high-dose infusions.
Source
Harm of IV High-Dose Vitamin C Therapy in Adult Patients: A Scoping Review — Critical Care Medicine · 2020




