AIDS Treatment News No. 017 (San Francisco Sentinel) - November 5,
In the last few weeks, Japanese researchers have found that a
component of ordinary licorice can stop the growth of the AIDS
virus in test tube cultures of human lymphocytes.
Many substances can stop the AIDS virus in the laboratory. But
this discovery, by a joint project of researchers at Fukushima
Medical College and Yamaguchi University Medical School, is
particularly important for the following reasons:
* The licorice ingredient, glycyrrhizin, is already clinically
used in Japan as an antiviral, especially for treatment of
hepatitis B. Good results have been reported.
* Side effects are mild to moderate.
* Concentrations of 50 ml per liter almost completely protected
human blood cells from the AIDS virus. We don't know the
concentrations reached during normal medical use of
glycyrrhizin, but the usual daily doses are 40 to 200 mg, and
much larger doses have been used.
* While many Japanese physicians use an intravenous
glycyrrhizin preparation apparently not available in the U. S.,
others have given it orally. Researchers believe that oral
administration can provide comparable doses (Fujiwara and
others, 1983). Apparently, physicians use the intravenous
preparation because it avoids other possibly unwanted
ingredients in licorice; includes other substances to minimize
the side effects of pure glycyrrhizin or of licorice; and helps
standardize the treatment by avoiding variability in absorption
from the digestive systems of different individuals.
* Licorice root, commonly available in health food stores and
in licorice candy, can deliver medically effective doses of
glycyrrhizin. These sources may provide a workable alternative,
should red tape impede clinical AIDS/ARC tests of glycyrrhizin
or U. S. availability of the Japanese pharmaceutical
The Japanese team announced its results on September 22, 1986,
and apparently reported them at a meeting of the Japanese
Society of Virologists on October 14. We have not yet seen any
report of that meeting, only a story in the JAPAN TIMES WEEKLY
(October 11), based on a telephone interview with Masahiko Ito,
a professor at Fukushima Medical College.
The team has not yet tested glycyrrhizin on persons with AIDS
The U. S. press has not picked up this story, and few
physicians have heard of glycyrrhizin or licorice as a
potential AIDS/ARC treatment. As far as we know, this SF
SENTINEL article is the first mention of it in any U. S.
Licorice and Glycyrrhizin
The most interesting ingredient in licorice is the chemical
glycyrrhizin (a word derived from the biological name of the
licorice plant, glycyrrhiza glabra). Glycyrrhizin, fifty times
sweeter than sugar, is responsible for the sweet taste of the
infusions, tinctures or other preparations made from the
licorice root. (The Chinese name for licorice is "gan cao",
meaning "sweet weed".)
Licorice also contains a number of other medically relevant
components, such as glycyrrhizic acid and glycyrrhetinic acid.
In one study, the latter showed a "remarkable" effect on the
Epstein-Barr virus, although glycyrrhizin itself had none
(Okamoto and others, 1983). Most of the Japanese studies used
purified glycyrrhizin instead of licorice for experiments and
for medical treatment. (We don't know if pure glycyrrhizin is
available in the U. S. Licorice root, and various extracts from
it, are available in health food stores or from herbalists.)
Medical Experiments and Uses
A recent Japanese study found that glycyrrhizin enhanced
interferon gamma production by human blood cells treated with
hepatitis B antigen or another immune stimulus (Shinada and
others, 1985). Glycyrrhizin alone did not cause the cells to
produce interferon. But pre-treatment with glycyrrhizin enabled
the cells to produce more interferon gamma (by a factor of as
much as eight) when they were challenged with an immune
stimulus (such as hepatitis B antigen). Collaboration between T
cells and macrophages was needed to obtain the greatest effect.
Interferon gamma is one of the experimental AIDS/ARC treatments
now being tried. According to one recent report (AmFAR,
September 1986), these trials have not produced much clinical
improvement. However, injecting interferon gamma may not have
the same effect as the use of glycyrrhizin to assist the body
in producing more of its own interferon as necessary.
Glycyrrhizin has shown antiviral activity in the laboratory
(Pompei and others, 1979), and has been widely used in Japan to
treat chronic active hepatitis B (Shinada and others, 1986).
The eminent herbalist, Subhuti Dharmananda, discussed licorice
in a paper on immunodeficiency syndromes (Dharmananda, 1986).
He reported that it has demonstrated both immune enhancing and
immune suppressive effects. Licorice has been used for treating
gastric ulcer and arthritis; traditional uses in Chinese
medicine have included treatment of laryngitis. But licorice is
almost always used in combination with other herbs in Chinese
To learn more about the traditional uses of the herb, we
consulted with Quan Yin Acupuncture and Herb Center of San
Francisco. They also recommended an herbalist, Brian K.
Weissbuch of KW Botanicals, in Fairfax, CA. Both explained that
while licorice is widely used in Chinese herbal formulas, it
generally constitutes only a small part of the preparation
(usually less than four percent). Our discussion with Mr.
Weissbuch largely concerned precautions and reasons for
avoiding indiscriminate use.
Cautions and Adverse Effects
A New Zealand study examined black licorice candy use among 603
high school students (Simpson and Currie, 1982). While these
researchers did not search for nor find ill effects among the
students, their paper provides a convenient summary of common
adverse effects of licorice reported up to that time.
The most common problems were high blood pressure, edema
(swelling, often of the ankles, wrists, or face), and muscle
pain, weakness, or paralysis. Most of these people had eaten
several hundred grams or more of licorice per week, often for
months or years. The effects ceased when they stopped using
licorice. Licorice acts as a natural cortisone, and may cause
sodium and water retention and potassium depletion. Doctors
have occasionally found severe or life-threatening reactions
requiring medical treatment.
The authors of the New Zealand study warn that person with
heart disease, high blood pressure (or a family history of high
blood pressure), or who eat a lot of salt or take certain
diuretics, should be especially careful of licorice.
Later studies have shown much greater risks to persons who are
taking insulin, or who have alcoholic cirrhosis. Even small
amounts of licorice can cause severe reactions.
The authors of the New Zealand study suggested that, for
healthy people, eating more than about 200 grams per week
(about one ounce a day) of black licorice candy sticks might
cause adverse health effects. Some kinds of licorice are
believed to have a stronger effect than the sticks. About five
percent of the high school students studied ate more than the
amount believed potentially harmful.
* One problem with licorice candy is that it is difficult to
determine how much licorice is being consumed. And the candy
has other ingredients, including oil from anise seeds, which
may cause untoward side effects in some people. It also has
sugar, molasses, or other sweeteners, and salt. Licorice
candies and liquors have caused a number of cases of medical
problems, as stated earlier. It may be safer to use the root,
which can be found in herb or health food stores and prepared
according to a practitioner's instructions, or according to
directions in herb books.
* What dose ought to be used? One book (John Lust, THE HERB
BOOK) suggests one teaspoon of the root, prepared as an
infusion, with one cup of water, and used slowly throughout the
day. One should check with a physician, practitioner, or at
least a good herb book before using licorice. It is clearly
advisable to tell one's physician what one is doing, even
though few physicians are familiar with medical uses or dangers
of licorice, and no one knows how it might affect persons with
AIDS or ARC.
* One particular caution: water retention can cause a sudden
weight gain of several pounds. This dangerous side effect which
can be caused by too much licorice or glycyrrhizin should not
be taken as a sign that the treatment is working.
* For those who want to gather licorice in the wild, Weissbuch
cautioned that many people confuse the licorice plant with wild
fennel, an entirely different plant.
To summarize, glycyrrhizin or licorice might help in treating
AIDS or ARC, although no one has tested it with patients at
this time. If one does try it, the advice we have been hearing
is to use caution, especially in long-term use, to avoid taking
too much, and to be aware of one's particular health problems
that may rule out the use of licorice, and of symptoms that
might be caused by its use.
This column will publish more information about glycyrrhizin or
licorice as treatments for AIDS or ARC, as it becomes
AmFAR. "Experimental drugs for AIDS and ARC: A directory of
clinical trials." The American Foundation for AIDS Research, 40
West 57th St., Suite 406, New York, NY 10019 (September 15,
Dharmananda, Subhuti. "A new herbal combination for the
treatment of immunodeficiency syndromes." Institute for
Traditional Medicine and Preventive Health Care, 2442 S. E.
Sherman, Portland, OR 97214 (1986).
Fujiwara, Y., Kikkawa, R., Nakata, K., Kitamura, E., Takama,
T., & Shigeta, Y. "Hypokalemia and sodium retention in patients
with diabetes and chronic hepatitis receiving insulin and
glycyrrhizin." ENDOCRINOL. JAPON., Vol. 20 (2), pp. 243-249
JAPAN TIMES WEEKLY. "Component halts AIDS virus growth"
(October 11, 1986).
Okamoto, H., Yoshida, D., & Mizusaki, S. "Inhibition of 12-O-
tetradecanoylphorbol-13-acetate-induced induction in Epstein-
Barr virus early antigen in Raji cells." CANCER LETTER, Vol. 19
(1), pp. 47-53 (May 1983).
Pompei, R., Flore, O., Marccialis, M. A., Pani, A., & Loddo, B.
"Glycyrrhizic acid inhibits virus growth and inactivates virus
particles." NATURE, Vol. 281, pp. 689-690 (1979).
Shinada, M., Azuma, M., Kawai, H., Sazaki, K., Yoshida, I.,
Yoshida, T., Suzutani, T., & Sakuma, T. "Enhancement of
interferon gamma production in glycyrrhizin-treated human
peripheral lymphocytes in response to concanavalin A and to
surface antigen of hepatitis B virus." PROCEEDINGS OF THE
SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE, Vol. 181, pp.
Simpson, F. O., & Currie, I. J. Licorice consumption among high
school students." NEW ZEALAND MEDICAL JOURNAL, Vol. 95, pp. 31-
33 (January 27 1982).