Does This Stuff Even Work? Yeah, Looks Like It Does.
Protecting ourselves in the worst case scenario.
If you get sick these days, you’re going to need more than NyQuil.
As the World Health Organization warns, "we have arrived in the post-antibiotic era," and we face a future pandemic up to 20 times worse than Covid. That future pandemic could be bird flu, mpox, or something else. On top of that, Covid continues to spread all year long, with new variants always evading vaccines. Research on Long Covid has stalled except for a handful of clinical trials.
But it's not hopeless.
Four years ago, we looked to plants to protect us from pathogens because vaccines and treatments weren't coming anytime soon. The minute those vaccines and antivirals came out, the public forgot all about plants. They reverted to their old assumptions that herbs were for hippies.
Well, here we are again.
Our vaccines and treatments are failing, and when they work they're often in short supply, or we can't get access to them.
As we mask while demanding clean air and better medicine, it's time to revisit those plants and see what they can do.
Do they even work?
Yeah, they do.
A 2024 review of studies in Viruses identified 10 different plant compounds with broad antiviral properties and effectiveness specific to Covid (and in many cases several other viruses). As they write, "plant-derived molecules can tackle viruses by acting on different aspects of their infection process" and "inhibit coronavirus/host protein pathways" by blocking them. The authors initially identified 45 different compounds and then narrowed them to the 10 most effective.
Plants work because they contain terpenoids, flavonoids, phenols, and alkaloids that all demonstrate "high anti-viral potential against SARS-CoV-2 particles" as well as other viruses. They do this in a variety of ways that work across variants because they block virus entry while also tamping down replication and essentially "stopping its life cycle." Sounds good to me...
Let's get into it.
First, ginkgo biloba contains two bioflavonoids called quercetin and rutin that can block Covid's 3CLPro BS PL-pro enzymes, as demonstrated in two different studies that looked at how they bind to parts of the spike protein. According to an article in Nature, 3CLPro plays a central role in virus replication, specifically for Covid. Ginkgo also contains kaempfero that inhibits Covid's envelope protein E, "consequently suppressing virus activity and proliferation." G. Biloba also brings an anti-inflammatory effect that can help with recovery as well.
Second, turmeric and curcumin "can either bind directly to the receptor binding domain of the viral S-proteins or secure ACE2 receptors of the hosted cell." Basically, they stop viral entry into your cells. As the authors write, a curcumin derivative called bi-demethoxycurcumin "displayed the best binding affinity" to spike proteins.
It also works on the original SARS virus.
Third, a common spice called artemesia annua demonstrated antiviral activity in clinical trials. The group who took an artemisia compound called artemisinin-piperaquine "took significantly less time to reach undetectable levels of SARS-CoV-2 than the controls." In fact, artemisinins "are known for their extended-spectrum antiviral activity." An artemisia derivative called artesunate has shown effectiveness against both DNA and RNA viruses including hepatitis and HIV.
Artemesia compounds work similar to ginkgo by latching on to five different parts of the spike protein "which might explain its remarkable binding affinity." In addition to flavonoids like quercetin, researchers have identified di-caffeoylquinic acid as doing a lot of the heavy lifting here. Like curcumin, these flavonoids also bind to ACE2 receptors on your cells and protect them. Medical researchers are working on refining these compounds into artenimol, a single high-potency compound for giving to patients.
Fourth, nigella sativa (black cumin seeds) have shown antiviral activity by disrupting viral RNA transcription. Carvacrol and nigellidine extracted from these seeds "can block ACE2 receptors, thus inhibiting the SARS-CoV-2 entry into the host cells."
Fifth, ginger (6-gingerol, 8-gingerol, 10-gingerol) can inhibit parts of the Covid spike protein. Specifically, it's the bioactive compounds geraniol, shogaol, zingiberene, and zingiberenol that do the blocking.
Sixth, garlic (allium sativum) shows antiviral activity. It contains compounds called allicin, ajoene, and garlicin that work against several viruses in the same ways as the other compounds, by targeting spike proteins, disrupting transcription, and protecting your cells' entry channels.
Next:
Cinnamon at 50 ug/ml operates the same way as the other compounds, by blocking host cell entry and viral replication. Rosemary (rosmarinus officinale) shows effectiveness in blocking viral activity, even in a study that compared it to the antivirals remdesivir and favipiravir. If you go this route, get ceylon cinnamon. Many common brands are cassia, and it’s toxic.
Want an unusual suspect?
It's dandelion.
Dandelion extract has shown to be "effective against influenza virus infection" and in higher concentrations "showed efficacy against spike proteins... and its different mutants" in human lung and kidney cells, while also helping to prevent the cytokine storm that's often so deadly in the acute stage. Here in particular, studies have shown that dandelion extract works regardless of the variant.
Finally, oregano (origanum vulgare) extract demonstrates antiviral activity against many DNA and RNA viruses, including Covid and HIV. As the authors write, extracts "showed remarkable efficacy against equine influenza virus, canine coronavirus, RS, and H1N1. In fact, it can inhibit up to 74 percent of viral activity at certain sites.
Again, carvacrol does the heavy lifting.
I've looked at other supplements and extracts with antiviral properties. They include grapeseed extract, grapefruit seed extract, olive leaf extract, echinacea, St. John's-Wort, and elderberry.
A 2024 study found that oleuropein, found in olive leaf extract, demonstrates high antibacterial activity at 130 mg/ml and high antifungal activity at 65 mg/ml. Another 2022 study found that oleuropein showed significant effectiveness against Covid in hospitalized patients when they were given 250-500 mg every 12 hours for five days. (No real difference between 250 and 500 mg.) The study also reviews previous research that oleuropein has shown effectiveness against other viruses, including HIV and influenza. It works the same way as other flavonoids, lectins, secoiridoids, and polyphenols, by blocking ACE2 receptors.
A 2022 study reviews available research on elderberry (sambucus nigra), confirming antiviral activity against HIV, flu, and coronaviruses. As the researchers write, adults in clinical trials "showed a significant reduction in symptoms, averaging 50 percent." Elderberry has also shown the ability to stimulate the production of immune cells. A 2019 study confirms that elderberry works against flu via "multiple modes of therapeutic action," including the inhibition of replication and host cell entry. An extensive 2021 study looking at prior research found that high-quality elderberry extracts enriched with anthocyanin work especially well.
A 2022 study in Nature found that a mixture of St. John's Wort (hypericum perforatum) and Echinacea showed significant antiviral activity against Covid. Specifically capsules with .9 mg of St. John's "can significantly reduce SARS-CoV-2 viral load," peaking at 36 hours after the start of treatment.
St. John's Wort works just fine on its own. The authors stress the importance of maintaining its concentration if you add other compounds like echinacea.
That said, a 2022 study in Frontiers in Pharmacology found that echinacea itself at 4,000 mg for 10 days led to a substantial reduction in viral load and fewer hospitalizations when used to treat Covid patients.
Now, here’s some news about metformin’s plant origins:
A 2024 study at the University of Minnesota found that metformin (derived from goat’s rue) significantly reduces viral load in patients while lowering the risk of rebound and Long Covid. That study confirms another one in 2023 that saw metformin reduce the risk of Long Covid by 41 percent.
Here’s the dosage they describe:
500 mg on day 1, 500 mg twice daily on days 2–5, then 500 mg in the morning and 1000 mg in the evening up to day 14.
It’s worth noting that metformin was originally developed in the search for antivirals against malaria and flu, so the recent studies make sense.
You can’t get metformin without a prescription, but you can buy goat’s rue, also known as galega (after the scientific name galega officinalis). It’s been used for centuries as a medicine, much the same way doctors prescribe metformin now. The recent studies on galega’s antiviral potential focus on guanidine, a compound found in plants that work like polyphenols and flavonoids.
Warning: Goat’s rue can be fatally toxic if you take too much. Metformin replaced early compounds like buformin and phenformin for this exact reason. So you’ll want to be careful with that one in particular. A study in Molecules explains that goat’s rue becomes toxic in foraging animals at .8 grams per 1 kilogram of body weight. The standard dose in alternative medicine comes in at 4 grams per day. In order to reach toxic doses found in livestock, a 140 lb person would need to take around 50 grams. A little math shows that the average recommended goat’s rue dose (4g) exceeds the amount of metformin used to treat Covid patients.
What else?
Studies have found antiviral potential in kudzu root. Even before the pandemic, a study in Retrovirology found that kudzu root extract fought HIV infection by inhibiting cell entry and could be added to a patient’s existing medicines. Kudzu contains puerarin, a compound that’s already used to treat diabetes, Parkinson’s, and cancer. A 2022 study in Frontiers in Immunology found that puerarin offers potential for Covid patients not only through its antiviral properties but also by moderating the immune system’s inflammatory response.
A 2020 study identified puerarin, along with quercetin and kaempferol, as very effective antiviral and immune system treatments.
A standard dose of puerarin lands at 200-400 mg per day, but one study on kudzu root for heart problems used 400-600 mg per day for up to 15 days.
The traditional Chinese herb Radix Bupleuri contains puerarin, quercetin, and kaempferol. It has shown strong antiviral effects against a range of diseases, and it’s been used for thousands of years.
The standard dose comes in at 3-10 grams per day. You don’t want to go over that amount, because like goat’s rue it’s toxic in higher doses.
So, that’s a lot of information to keep straight.
Here's a chart:
You can look up most of these supplements and extracts on Mount Sinai's health library. You can also visit sites like Drugs.com to start gathering information. Both sites give excellent information on possible side effects and drug interactions. You can also look at Stephen Harrod Buhner’s Herbal Antivirals.
Now for the caveats:
The studies linked in the sheet provide the most detailed dose information I can find. Duration runs around two weeks for an acute illness and 3-4 months for chronic infections. It's important to talk with a doctor if you're skeptical or not sure about interactions with other drugs, or you can look at the studies on your own. Supplements in general can be hard on your liver and kidneys, especially if you take them for prolonged periods.
Some self-proclaimed experts and gatekeepers of the medical establishment love to scoff at the idea of using plants to treat infections, even when plants form the foundation of modern medicine. I think it’s elitist and hypocritical for them to sit back in judgment, doing so little to help while the Covid crisis continues to spiral out of control and ruin countless lives. As I’ve written elsewhere, if treatments were accessible, we would take them.
Obviously, you can add other vitamins and minerals to this list. I’ve written about vitamins and minerals that help your immune system here.
This post focuses specifically on antivirals.
Do I think it's sustainable to take high amounts of supplements all year long to ward off all kinds of airborne diseases, for the rest of our lives? Not really. That's why we absolutely need clean indoor air, masks, better vaccines, and better treatments. We also need the FDA and NIH to start doing their jobs by funding and organizing clinical trials on these affordable, effective antivirals.
Until then, at least we have this information.
Here's a list of the studies:
So there you have it.
If you've been wondering whether this stuff really works, the answer appears to be a loud yes. We need more research on dose amounts, but the studies all point in the direction of taking as much as you can while staying within the safe limits, for the duration of any time you feel at risk of getting sick.
Most of these extracts work against multiple viruses. They also help regulate your immune system and push it toward a less inflammatory response.
That's good to know.
My family has been using some of these supplements for several years, and it might explain why we've managed to steer clear of Long Covid. We still wear N95 masks everywhere. We advocate for clean air and better vaccines, along with better treatments. In the meantime, it looks like we can up our supplement game and that it's actually going to bring some benefit.
This isn't magic.
These plant compounds work the same way as many of the antivirals on the market. Medical researchers have been researching the antiviral properties of plants for decades, and cultures have used them for thousands of years. Given our current outlook, they're worth taking seriously.
Use what you can.
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