Flu - Herbal Medicine/Phytotherapy
The Flu - Herbal Medicine/Phytotherapy page is regularly updated as new evidence appears in the medical journals.
The Flu - Herbal Medicine/Phytotherapy page lists natural herbal substances that have been shown to have potential for either preventing flu , shortening the duration of a flu infection or reducing the severity of flu symptoms.
CHINESE SKULLCAP (SCUTELARIA BAICALENIS)
(Note: this is a totally different plant to American Skullcap)
The root of Chinese Skullcap contains the flavonoids baicalin, wogonin and baicalein. Most studies have been conducted on these flavonoids rather than the entire herb. A 2013 trial on the inhibitory power of baicalein on influenza A virus subtypes, found that it significantly inhibited in vitro replication of the viruses using plaque reduction assays. The study concluded that “a combination of low-dose baicalein with other anti-influenza agents could be applicable for development of alternative remedies for treating influenza A virus infection.”
BAYBERRY (MYRICA RUBRA)
Bayberry, also known as wax myrtle or candleberry, is a Native American remedy used as a stimulant for the body’s defence mechanisms against coughs, colds, flu, fever, headache and sore throat. Either the bark or the leaf is usually brewed into a spicy tea. A 2008 study of the anti-influenza activity of myrica rubra leaf extract found that it showed activity against both type A, its subtype H3N2, and type B influenza.
BLOODY GERANIUM / BLOODY CRANESBILL (GERANIUM SANGUINEUM)
South African tries have used Bloody Geranium as a natural antibiotic for centuries. In folk medicine it is specifically used to treat upper respiratory tract infections, coughs, and ear, nose and throat infections. It is also said to speed recovery from bronchitis, flu and colds.
In a 2008 study on Geranium Sanguineum’s effects on influenza infection, extract was shown to have a pronounced protective effect of up to 70.1%. It also slowed growth of the virus and aided swift recovery. Further human trials are proposed.
BLACK CHOKEBERRY (ARONIA MELANOCARPA)
Dried Aronia berries or juice have been traditionally used by Potawatomi Indians to cure colds. A 2013 study which was attempting to develop a new broad spectrum anti-influenza agent to combat resistant strains, found that Aronia berries contained several polyphenolic constituents, two of which – ellagic acid and myricetin – had strong anti-influenza properties. It was concluded that ellagic acid and myricetin have potential in influenza therapies.
ELDERBERRIES (SAMBUCUS NIGRA)
Black Elderberry extract, Sambucol, looks set to be another super flu fighter if it is taken when symptoms first appear. Studies at the University of Arizona, the University of Oslo and in Israel all showed impressive treatment statistics with up to 90% of patients becoming symptom free within 72 hours, while a placebo group did not recover for at least six days and took more painkillers and nasal sprays.
A 2011 study using a standard elderberry extract (Rubini BerryPharma AG) found it to be active against human pathogenic bacteria as well as influenza viruses.
Properly structured trials on the effects of ginseng on viral infections are not easy to find, but both the American and the Korean root have been demonstrated to have various immunomodulatory functions. The results of a study of the effects of ginseng on mice infected with type A influenza showed that ginseng extract has multiple action mechanisms against infectious diseases. From this researchers concluded that a normal intake of ginseng would be likely to have beneficial effects on preventing influenza virus infections.
It seems as if you can boost immunity by getting into a green cuppa. In 2011 BMC Complementary and Alternative Medicines reported on a randomised, double-blind, placebo-controlled study of 200 Japanese healthcare workers. Most had been vaccinated against flu, but in addition half received capsules of a green tea extract that contained the compounds catechins (378mg per day) and theanine (210mg per day), while the other half received a placebo. After five months the incidence of influenza in the green tea group was significantly lower than that of the placebo (4 versus 13 cases).
Japanese Mushrooms – AHCC
Results of a human clinical study recently published in the journal Nutrition Research, claim that AHCC – an extract from the room of Japanese medical mushrooms – can boost the effectiveness of the flu vaccine.
In a trial of 30 adults who received the flu vaccine, the half taking AHCC had higher levels of infection-fighting white blood cells than those taking a placebo
A previous study at Yale Medical School also demonstrated that AHCC improved immune response in elderly people.
Indian Echinacea (Andrographis paniculata)
All parts of the Echinacea plant have been used as folk remedies for colds and flu viruses, however evidence is scant. A review of trials as a common cold preventative found that there was a drop of 30% in the likelihood of contracting one if Echinacea was being taken. However the trials all used different preparations and had varying results.
In a 1999 randomised double blind placebo study in Valdivia, Chile, a group of 158 adults received either 1200mg per day of Andrographis paniculata dried extract, or a placebo as a treatment for common cold. The Andrographis paniculata group enjoyed a significant decrease in symptoms by Day 4 over the placebo group.
Japanese Plum / Chinese Apricot (Prunus Mume)
A 2008 study published in Biological & Pharmaceutical Bulletin, reported that ingesting fruit juice concentrate of Japanese plum had a strong anti-influenza effect against type A viruses. However, it did not reduce symptoms once the virus had been contracted. Researchers believe that the lectin-like qualities of the plum juice allowed it to bind to substances in the blood and prevent the host from becoming infected.
Licorice (Glycyrrhiza glabra)
Licorice softens mucous membranes in the throat, lungs, stomach and intestines. It cleanses inflamed mucous membranes making it a potent healing agent for tuberculosis. In a 2008 study on the antiviral effects of licorice it was found to reduce hepatocellular damage in Hepatitis B and C patients and reduce viral activity in patients with influenza virus A pneumonia. In a 2013 study Glycyrrhiza glabra was found to act as a strong cough suppressant which could be used as a natural substitute for synthetic cough suppressants which have been linked with numerous unpleasant side effects.
In Chinese medicine this dried root has been used as a preventative and treatment for viral infections ranging from flu to HIV. In a 2013 study it was investigated as a treatment for H9N2 (avian influenza) with some success. Researchers found Milkvetch reduced virus replication and promoted immune responses.
Narcissus / Chinese daffodil (Narcissus tazetta)
In a 2010 trial a mannose-binding lectin was extracted from the bulbs of Narcissus tazetta (NTL) and found to have potent antiviral activity especially against influenza A and B with IC50 values ranging from 0.20 microg/ml to 1.33 microg/ml in a dose-dependent manner. The antiviral activity of NTL is mainly expressed in the early stages of the viral cycle.
Paashaanbhed / Praschabhed (Bergenia ligulata)
A rhizome plant used in Nepalese folk medicine, in a 2003 trial extract from Bergenia ligulata was found to inhibit the in vitro replication of the influenza virus in a dose dependent manner. It inhibited viral synthesis by the presence of condensed tannins in the extract.
Pandan leaves (Pandanus amaryllifolius)
In a 2004 study, a lectin, christened Pandanin, was isolated from the saline extract of the leaves of Pandanus amaryllifolius. This extract was shown to have antiviral reactions against herpes simplex virus type 1 and influenza virus H1N1. Within 3 days EC50 of 2.94 and 15.63 micromM respectively.
Rockrose (Cistus incanus)
Medicines from this evergreen shrub are commonly used in Bach flower remedies for anxiety or to promote relaxation. A 2009 study looked at the antiviral activity of polyphenols contained in cistus extract against cold and flu viruses. In a randomised placebo-controlled study of 160 patients with upper respiratory tract infections, those treated with the cistus extract (CYSTUS052) reported a decrease in symptoms that was more distinct than those treated with a placebo.
Vishapacha / Vishahari (Clinacanthus siamensis)
A 2009 study of ethanolic extracts from 20 medicinal plants found that the Clinacanthus siamensis leaf had the highest in vitro antivirus activity. Results suggested the extract had a protective effect against the influenza virus.
Ginger (Zingiber officinale)
A Japanese study led by Dr. Hiroshi Ochiai into the effectiveness of ginger to prevent influenza found that the root activated a chain reaction in our immune system that helped destroy viruses and inhibit their replication. However a 2006 study found no inhibitory effect on the growth of influenza although there was some belief that it could exert an effect through macrophage activation.
Folk remedies for using ginger to combat sore throats involve making a warming tea from fresh ginger, honey and lemon juice.
Myrobalan (Terminalia chebula retz)
Traditionally Myrobalan or Black Alder is used to treat coughs, sore throat, fever and inflammatory disorders. In a trial on the multicomponent herbal formula hedretan-96 for antiviral activity against influenza type A, of the 23 components in the formula only Terminalia chebula was found to have a significant protective effect. However, results indicated that the complete formula offered improved antiviral activity over Terminalia chebula extract alone.
Lopez root (Toddalia asiatica)
In a 2005 study over 200 Chinese medicinal herbs were screened for antiviral effects against influenza. Toddalia asiatica showed the strongest activities against H1N1 virus. It is being considered as a candidate for an anti-influenza type A virus agent.
The Flu - Herbal Medicine/Phytotherapy page is not exhaustive and will be updated regularly as new evidence appears.