Anecdotal information and case reports suggest that intravenously administered vitamin C is used by Complementary and Alternate Medicine (CAM) practitioners. The scale of such use in the U.S. and associated side effects are unknown.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/vitamin-c-intravenous-use-complementary-and-alternative-medicine-practitioners-and
[2] http://admin.indiaenvironmentportal.org.in/category/author/sebastian-j-padayatty
[3] http://admin.indiaenvironmentportal.org.in/category/author/andrew-y-sun
[4] http://admin.indiaenvironmentportal.org.in/category/author/qi-chen-et-al
[5] http://admin.indiaenvironmentportal.org.in/category/journal/plos-one
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-personnel
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/drugs
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/research
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us