Data from clinical trials comparing Fluzone to Fluzone High-Dose among persons aged 65 years or older indicate that a stronger immune response (., higher antibody levels) occurs after vaccination with Fluzone High-Dose. Whether or not the improved immune response leads to greater protection has been the topic on ongoing research. A study published in the New England Journal of Medicine indicated that the high-dose vaccine was % more effective in preventing flu in adults 65 years of age and older relative to a standard-dose vaccine. The confidence interval for this result was % to %. A separate study published in The Lancet Respiratory Medicine reported that more immunogenic, high-dose vaccines can reduce the number of hospital admission for people aged 65 years or older, especially those living in long-term care facilities. The study compared hospitalization rates among more than 38,000 residents of 823 nursing homes in 38 states during the 2013-14 flu season.
The high doses of vitamin C required to be effective for cancer treatments (15 to 100 grams/infusion) may only be given by an intravenous route. Oral administration of a dose this high would not be tolerated or absorbed by the gastrointestinal tract. Many intolerable side effects would occur with oral doses anywhere near these levels. IV infusions of high doses of vitamin C along with various other antioxidants and nutrients may be given to assist in treating various cancers. High doses of vitamin C given intravenously have very few side effects.