Ingredients:
Astragalus [Astragalus membranaceus (Fisch. ex Link)
Bunge] root
Eleuthero (Siberian ginseng) [Eleutherococcus senticosus
(Rupr. & Maxim.) Maxim.] root
Asian ginseng (Panax ginseng C.A. Meyey) root
Stephania (Stephania tetrandra S. Moore) root
Echinacea [Echinacea purpurea (L.) Moench] root
Barrenwort (Epimedium grandiflorum C. Morren) leaf and
flower
Dong quai [Angelica sinensis (Oliv.) Diels] root
Resistex® is manufactured and distributed by Botanica BioScience
Corporation. Each capsule contains 450 mg of a proprietary blend of
Echinacea purpurea root and extracts of astragalus, eleuthero (Siberian
ginseng), Asian ginseng, stephania, barrenwort, and dong quai.
The Resistex formula was developed with the intention of providing
resistance to infection with colds or flu. The initial cause of a cold
or flu is a viral infection. Colds are caused most commonly by a
rhinovirus and less often by a coronavirus. The influenza viruses
cause the flu. In theory, bolstering the immune system can prevent
disease or reduce symptoms. A number or herbal preparations have
been promoted as immunostimulants for this purpose, including
those containing echinacea and/or eleuthero (Wagner, 1997). Other
herbs have been described as adaptogenic, i.e., substances that assist
in nonspecific heightened resistance to stress. The adaptogenic properties
of these herbs may be due, in part, to antioxidant and/or
immunomodulatory activity (Davydov and Krikorian, 2000). Herbs
with adaptogenic activity ascribed to them include eleuthero, Asian
ginseng, ashwaganda, astragalus, and schisandra (Davydov and Krikorian,
2000; Wagner, Nörr, and Winterhoff, 1992; Wallace, 1998).
Cold and Flu (Prevention)
An open, placebo-controlled clinical trial with 61 participants
found Resistex to significantly reduce the incidence of colds and flu
compared to recall of the previous season. Subjects were divided into
three groups and given one or two tablets of Resistex or placebo.
Treatmentwas initially for four weeks, followed by a one-week intermission,
which was followed by several two-week treatment periods,
each separated by one-week intermissions. The total trial length was
four and a half months. As a result, the group that received two tablets
Resistex (900 mg daily) had a 67 percent reduction in the incidence of
colds and flu compared to the previous season. In comparison, the
group that received one tablet (450 mg daily) had a 43 percent reduction,
and the placebo group had a 14 percent reduction (Wang, 1998).
Methodological flaws, such as the dependence on recall for the previous
season’s incidence of colds and flu, and lack of detail in the trial
report led our reviewer, Dr. Richard O’Connor, to rate the clinical
outcome of this trial as undetermined.
No side effects were reported in a controlled clinical trial with 61
patients that used a dose of 900 mg per day (Wang, 1998).
