Intravenous Vitamin C
Vitamin C is in the news again. A study
carried out by a research team from the Harvard School of Public
Health and published July
1 in the New England Journal of Medicine (Fawzi,
WW, 2004) showed that a multivitamin supplement that included vitamin
slowed the onset of AIDS and provided an "effective, low-cost
means of delaying the initiation of antiretroviral therapy in HIV-infected
women." The total cost of the treatment was estimated by
the researchers to be about $15 per year. Here is yet another demonstration
of the astonishing power of food supplements, particularly antioxidants
such as vitamin C, to promote human health.
I am often asked whether or not vitamin C (ascorbic acid) is also
an effective way of fighting cancer. I answer that while there is
a growing body of scientific evidence to suggest that vitamin C is
useful in the prevention of cancer, the jury is still out on its
effectiveness as a cancer treatment. However, its low cost and astonishing
lack of toxicity make it an extremely attractive candidate for further
Representative of the investigations that are currently underway
concerning vitamin C's role in the treatment of cancer is the
work of Kedar N. Prasad, PhD, a professor of radiology at the University
of Colorado Health Sciences Center, Denver. Prasad has demonstrated
that vitamin C is capable of inhibiting the growth of cancer cells
in vitro. He advocates giving vitamin
C and other antioxidants to patients while they are undergoing conventional
radiation. (I draw on his work in my book Antioxidants
Prasad's theory is that normal cells require only a minute,
precisely controlled amount of antioxidants in order to function.
They reject any excess. But among other defects, malignant cells
have lost the capacity to regulate their uptake of antioxidants such
as vitamin C and E. Antioxidants can therefore accumulate in cancer
tissue in levels that can lead to the breakdown and death of malignant
cells (Prasad 2003).
The history of research into vitamin C as a cancer treatment is clouded
with controversy. In the 1970s, a Scottish physician Ewan Cameron,
MD, teamed up with Linus Pauling, PhD, to write a book, Cancer
and Vitamin C, in which they extolled
the usefulness of vitamin C as a treatment for cancer. (Pauling had
previously published a book
on vitamin C and the common cold.) Cancer
and Vitamin C became a
bestseller and this fueled public demand for investigation of the
role of vitamin C in cancer treatment.
Pauling was a world-famous chemist, a two-time Nobel laureate, with
great medical achievements to his record. But he was not a medical
doctor, and this raised the ire of some medical critics such as the
self-proclaimed "quackbuster" Victor Herbert, MD. However,
the demand for a fair test of Pauling's thesis could not be
ignored indefinitely, and in time doctors at the Mayo Clinic, Rochester,
MN, undertook a clinical trial that was supposed to replicate Drs.
Cameron and Pauling's protocol.
In two often-cited papers, Charles Moertel, MD and his Mayo colleagues
claimed that vitamin C had absolutely no beneficial effect when used
in the treatment of patients with advanced cancer, regardless of
whether or not they had received prior chemotherapy (Creagan 1979
and Moertel 1985). Dr. Moertel was called the "foremost professional
demolition expert...of alternative cancer treatments" (Richards
1991). Moertel's negative comments on the topic included his
assertion that evaluating alternative treatments was a "waste
of time and money...a waste of patient hope" (Moertel 1989).
His high-handed manner of testing vitamin C convinced proponents
that they had been set up for inevitable defeat. But the damage had
been done, and vitamin C was marginalized as a cancer treatment.
Tale of Two Trials
Is there a good scientific reason why vitamin C might have failed
to show a beneficial effect in the Mayo Clinic trials while succeeding
in the hands of its proponents? It now appears that there was.
In the Mayo Clinic studies all patients received either vitamin
C tablets or an inert sugar pill. What was widely overlooked at
the time was that patients on the Cameron-Pauling protocol were
given vitamin C not only orally but also via intravenous injection.
A few practitioners – most notably Abram Hoffer, MD of Victoria,
British Columbia and Hugh Riordan, MD of the Center For the Improvement
Of Human Functioning International in Wichita, Kansas – continue
to use vitamin C intravenously at doses of up to 100 grams – almost
4 ounces – per day. In fact, using high-dose intravenous vitamin
C has become a common procedure among CAM-oriented doctors, although
it is ignored by orthodox medicine – witness the fact that
in the decade since 1994 the number of presentations on intravenous
vitamin C at the American Society of Clinical Oncology (ASCO) convention
has been exactly zero.
New NIH Data
Could the route of administering vitamin C make a significant difference?
Yes it could. New data shows that how one gives ascorbic acid has
a big impact on the amount that actually becomes physiologically
available. An April, 2004 study by scientists at the US National
Institutes of Health (NIH) showed that much more vitamin C gets
taken up when it is given via the intravenous route than when the
vitamin is taken orally. The authors of the study include Sebastian
J. Padayatty, MD of the Molecular and Clinical Nutrition Section
at one of the NIH institutes, and his chief, Mark A. Levine, MD.
Both are highly regarded figures in academic circles. Dr. Levine
is a Harvard Medical School graduate who carried out the laboratory
work that convinced the National Academy of Science to increase
the recommended daily allowance (RDA) of vitamin C. (In 2000, the
RDA for men was increased from 60 to 90 mg daily, and for women
the RDA was increased from 60 to 75 mg daily.)
In the Padayatty study, 17 healthy hospitalized volunteers were given
either oral or intravenous doses of vitamin C, and blood plasma levels
were calculated for a dose range of 1 to 100 grams. The authors reported
that "peak plasma vitamin C concentrations were higher after
administration of intravenous doses than after administration of
oral doses...and the difference increased according to dose."
In fact, the blood concentration of Vitamin C when given intravenously
was 6.6 times greater than when the same amount was given orally.
However, this hardly tells the full story. The maximum tolerated
doses also differed significantly according to whether the vitamin
C was administered orally or intravenously. The maximum tolerated
oral dose was calculated to be three grams every four hours, but
when the vitamin C was given intravenously the researchers found
they could give a 50 gram dose in the same period. Furthermore, plasma
concentrations up to 60 times greater could be achieved using the
These NIH scientists observed that oral vitamin C "produces
plasma concentrations that are tightly controlled.… Only intravenous
administration of vitamin C produces high plasma and urine concentrations
that might have antitumor activity." They conclude that "the
efficacy of vitamin C treatment cannot be judged from clinical trials
that use only oral dosing," as the Mayo Clinic studies most
conspicuously did, and that "the role of vitamin C in cancer
treatment should be reevaluated" (Padayatti 2004). Coming from
such prestigious government scientists, publishing in the Annals
of Internal Medicine, I believe this is a convincing (albeit belated)
refutation of the poorly designed Mayo Clinic studies.
It is never easy to arrange clinical trials, especially of an agent
that has long been in the public domain and from whose sale no super-profits
can be expected. The way the drug approval system works in the United
States virtually requires the enthusiastic support of sponsors with
deep pockets (which almost invariably means a pharmaceutical company)
in order to see a new drug through the long, involved and expensive
process of drug approval. No non-toxic, readily available agent has
ever been approved by the Food and Drug Administration for the treatment
of cancer. Vitamin C at retail sells for around five cents per gram.
The cost of even 100 grams prepared for intravenous use is still
very inexpensive compared to patented chemotherapy. I therefore don't
think you will find many drug companies lining up to test and market
such a readily available agent. And so the question of what vitamin
C can do for patients – so fascinating and promising – has
remained in limbo.
However, things may be about to change. At a meeting of the American
College for the Advancement of Medicine (ACAM) in April, 2003, Jeanne
A. Drisko, MD, announced just such a clinical trial at her institution,
the University of Kansas Medical Center. Luckily, the Cancer Treatment
Research Foundation (CTRF) stepped forward to fund the Kansas City
clinical trial. A randomized controlled trial, with Dr. Drisko as
principal investigator, is now underway at the University of Kansas
Medical Center, evaluating the safety and efficacy of antioxidants
when added to chemotherapy in newly diagnosed ovarian cancer (Drisko
In a recent letter, Dr. Drisko wrote: "This is a randomized
study in newly diagnosed ovarian cancer (Stage III or IV). The study
subjects are randomized to receive either first-line chemotherapy
or first-line chemotherapy along with high-dose antioxidants. The
antioxidants are given both orally and intravenously. If randomized
to the antioxidant arm, patients receive daily oral vitamins A, C,
E and carotenoids, and intravenous (IV) vitamin C 2 times per week
for 12 months. We tailor the dose of the IV vitamin C to their plasma
vitamin C level – we try to get...the neoplastic cell kill
dose, using Dr. Hugh Riordan's protocol.
"At this plasma level, vitamin C is chemotoxic to the cancer
cells and appears to be non-toxic to healthy cells. But we are following
white cell and platelet counts and other markers for possible toxicity
from the vitamin C. Most patients need between 75 and 100 grams infused
to get to that plasma level. We can assure concerned oncologists
that it preliminarily does not appear that the high-dose antioxidants
are interfering with the chemotherapy at this time.
In ovarian cancer," she continued, "the patients are
usually treated with chemotherapy during the first 5 to 6 months
(6 cycles of carboplatin and paclitaxel) so they are getting an additional
6 to 7 months of antioxidants past the chemo. This study is conducted
under the oversight of the FDA with an Investigative Drug (IND) number
and has approval from the Human Subjects Committee (i.e., the institutional
review board) of the University of Kansas Medical Center. So far,
we have 14 patients enrolled and are hoping to recruit 40. We have
had 2 dropouts: One because she refused to adhere to the treatment
requirements and started smoking, and one because she was chemotherapy
resistant to all chemotherapy by drug assays" (Drisko 2004).
This trial is a very encouraging development. Dr. Drisko is a person
with credibility in both orthodox and CAM circles. She is thus in
an ideal position to do a study that will be not only rigorous but
entirely believable in its conclusions.
As some readers know, I wrote the authorized biography (Free
of Albert Szent-Gyorgyi, MD, PhD, who won the 1937 Nobel Prize for
his discovery of vitamin C. In fact, it was he who named the vitamin
ascorbic acid and first predicted its use in cancer. When Szent-Gyorgyi
was on his deathbed, at the age of 93, Linus Pauling flew from California
to Szent-Gyorgyi's home at Woods Hole, Mass., to say goodbye.
Holding his hand, Linus said wistfully, "You know, Albert,
I always thought that someday we two would work together." Szent-Gyorgyi
looked up and said, humorously, "Well, if not in this life,
then maybe in the next." Pauling himself died a few years later,
also at age 93. They were two of the greatest thinkers of the 20th
century and it was one of the great privileges of my life to know
them both. I like to think of the two of them smiling down at this
latest development in the fascinating saga of this amazing chemical.
To find out more about the Kansas clinical trial of vitamin C,
Jeanne Drisko, MD, Associate Professor
Program Director, Program in Integrative Medicine
Functional Medicine and Complementary and Alternative Therapies
University of Kansas Medical Center
Kansas City, Kansas 66160 USA
American College of Physicians (ACP). How vitamin C is administered
affects how much reaches the bloodstream and may affect the results
of studies of its potential effect on cancer. Annals
of Internal Medicine, Summaries for Patients, April 6, 2004. Retrieved July
1, 2004 from: http://www.annals.org/cgi/content/full/140/7/533
Drisko JA, Chapman J, Hunter VJ. The use of antioxidants with first-line
chemotherapy in two cases of ovarian cancer. J
Am Coll Nutr. 2003
Drisko JA. Personal communication, July 1, 2004.
Fawzi WW, et al. A randomized trial of multivitamin supplements and
HIV disease progression and mortality N
Engl J Med 2004;351:23-32.
Moertel, C.G. Interview on 'Health Report,' ABC National
Radio, August 7, 1989 [cited in Richards].
Padayatty SJ, et al. Vitamin C pharmacokinetics: implications for
oral and intravenous use. Ann Intern Med. 2004 Apr 6;140(7):533-7.
Prasad KN. Antioxidants in cancer care: when and how to use them
as an adjunct to standard and experimental therapies. Expert
Rev Anticancer Ther. 2003 Dec;3(6):903-15.
Richards, Evelleen. Vitamin C and Cancer:
Medicine or Politics? New
York: St. Martin's Press, 1991.