Scientific research has established that several herbs and herbal combinations will inhibit flu viruses of various strains. In this article we will cover the research on these plant medicines.
How do they do this? The research has confirmed that certain medicinal herbs and their constituents can directly inhibit virus replication. Some also stimulate the body’s own immune system in order to counteract the flu virus.
The research findings have confirmed these effects that nature produces from certain medicinal herbs. This has to do with a two-pronged effect:
1) The ability of these herbs and their phytochemicals to stimulate the body’s own immunity, allowing the body to be able to more effectively fight off the infection;
2) The ability of the independent constituents within the herbal medicine to shut off a virus’ ability to replicate, even in a sterile environment outside the body.
Moato formula treats influenza
In a 2017 study, researchers from Japan’s Fukuoka University School of Medicine confirmed that a Japanese herbal medicine called Maoto inbibits the influenza virus. The researchers cultured influenza A strains, including H1N1 and H3N2, in the laboratory. When they applied the Maoto herbal medicine, they found it successfully inhibited the replication of the viruses.
In a 2012 clinical study from Japan’s Ohmura Hospital in Chiba, 150 patients with influenza A were treated. They were split into three groups. One group of the patients was given an herbal medicinal combination called Maoto. Another group was given Oseltamivir. Another group was given Zanamivi. The fourth group was given Oseltamivir and the Maoto herbal medicine.
The group given the Oseltamivir with Maoto had the shortest flu duration, but for those who were five years old or younger, the Maoto alone resulted in the least flu duration.
The flu duration among those patients given both the Maoto and Oseltamivir was 31 hours.
Those patients given the Maoto only who were five or younger had an average duration of 33 hours, versus 61 hours among those patients treated only with Oseltamivir. For Influenza B patients, the Maoto herbal combination was on par with the conventional treatments.
Another 2012 study of 28 flu patients treated 10 with Maoto, 10 with Zanamivi and 8 with Oseltamivir. This study found that all three treatments worked about the same in terms of symptom scores and shortened durations.
What herbs are in Maoto?
The Japanese Maoto combination is composed of Ma Huang (Ephedra), Apricot Kernel, Cinnamon Bark and Licorice – also called Glycyrrhiza Root. Each of these herbs have been clinically utilized in different combinations by Traditional Chinese Medical doctors for stimulating immunity and inhibiting viruses.
Forsythia and Honeysuckle fight the flu
The most recent finding is from China’s Northwest A&F University. Here researchers determined that two medicinal herbs known for clinical success in influenza treatment, and at least fifty phytochemicals contained in them, can inhibit the growth of the flu virus.
The researchers tested two different herbs that are known in Chinese Medicine to inhibit viruses: Fructus forsythiae (also called Forsythia or Lian Qiao) and Lonicera japonica (also called Suikazura, Jinyinhua and Japanese Honeysuckle). The researchers exposed these herbs and their constituents to influenza viruses and human cells within a laboratory setting.
The researchers found that these two herbs, and fifty of their constituents – phytochemicals that were isolated from them – significantly inhibited the replication of the viruses.
A 2017 study from the University of Hong Kong studied the compound called forsythoside A from the Forsythia suspensa plant. They found the compound significantly inhibited different influenza strains in both lab cells and mice. They found the plant chemical interfered with the budding process of the virions.
This study follows other research concluding similar findings with other herbs.
The researchers concluded:
“The overall data suggest that the medicinal herbs function by indirectly suppressing the virus proliferation via regulating the immune systems in hosts, and also, by directly inhibiting virus proliferation through targeting viral proteins essential for the viral life cycle.”
Napal smartweed for influenza
Another recent study, from Shandong University’s School of Pharmaceutical Sciences, has determined similar results with another plant, Polygonum nepalense (also called Napal smartweed). Polygonum nepalense is also known for effectively treating influenza.
The researchers found that six polyphenols within the herbs – kaempferol, glucopyranoside, quercetin, pyrogallol, gallic acid and epipinoresinol – all effectively reduced infective inflammation.
Lomatium dissectum for flu virus
We add to this the Native American legend of Lomatium dissectum. According to the legend, Ernst Krebs, M.D. of Carson City observed that the Washoe Indians of Nevada seemed to recover quickly and avoid the plague of the 1918 influenza by taking an herbal medicine called “Toh-sa.” Dr. Krebs named it Balsamea, as it smelled like balsa. It was later named Leptotaenia dissecta and then Lomatium dissectum by botanists.
Consistent with this legend, in 1995, the root of Lomatium dissectum was tested for antiviral activity at Canada’s University of British Columbia. The Lomatium was found to inhibit the “cytopathic effects” of rotavirus.
Lomatium is only one herb from one traditional medicine among hundreds of herbs and hundreds of traditional medicines around the world. The effective inhibition of influenza by fifty constituents isolated from the two herbs in the new laboratory study from China illustrate that there are many anti-influenza herbal medicines, even besides the Maoto combination. Many of the fifty anti-influenza constituents found in Fructus forsythiae and Lonicera japonica also occur in other herbal medicines.
Eupatorium fortunei inhibits influenza
Eupatorium fortunei has been used in Asia for virus infections for centuries. A 2017 study from Korea’s Chungnam National University found that Eupatorium fortunei significantly reduced viral replication for influenza A virus, the Newcastle disease virus, and vesicular stomatitis virus.
The researchers concluded:
“Thus, WEF [water extract Eupatorium fortunei) and its active components are immunomodulators of the innate immune response in murine macrophages, a finding that is potentially useful to developing prophylactic or therapeutic treatments against a range of viruses.”
Undiscovered antiviral herbs
These herbs studied present only the tip of the iceberg among herbs that have been used among various traditional medicines around the world. There are a variety of herbs that are known to stimulate immunity, giving the immune system a stronger ability to fight off various infections.
In 2011, a Cochrane Review of Research from the Beijing University of Chinese Medicine found among 26 studies that several Chinese herbal medicines “demonstrated positive effect on fever resolution, relief of symptoms, and global effectiveness rate” for influenza. The research concluded, however, that more clinical research was necessary to confirm certainty.
Influenza epidemics have taken the lives of many, and hospitalized thousands. Most of those have been characterized as being immunosuppressed – their immune systems were weakened, either by another infection or a general lack of immunity.
The role of herbs in this and any other epidemic is not only to prevent replication of the virus. It is also to stimulate the immune system to respond to these infective viruses.
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