We are reaching a crisis in modern healthcare, and the entire paradigm of how we manage human and animal infections is being questioned. The fear is that our saviour, the antibiotic, is now causing more harm than good. Antibiotics have undoubtedly saved millions of lives but the assumption that they are safe has led to their overuse and, as a result, increased microbial resistance.

MRSA, C. difficile and E. coli are just a few well-known examples of microbes showing antibiotic resistance. Given the levels of antibiotic use, it is perhaps no wonder that this is happening. In the USA, for example, by the time the average 18 year old leaves school he or she will have received 10–20 courses of antibiotics. Meanwhile, most intensively reared farm animals receive antibiotics when they are not even ill as a cheap form of insurance to prevent the spread of disease when stocking levels are high. Pigs receive up to eight of antibiotics in their short six-month life. In Britain 42% of all antibiotics are given to farm animals, and 80% of these are put into feed or water to treat a whole flock or herd at once. The widespread use of antibiotics in farming is a significant contributor to the problem of resistance among humans too.

The perception of antibiotics as a kind of magic bullet and their consequent proliferation is having three dramatic effects: escalated antibiotic resistance, a disturbed microbiome, and disrupted immuno-neurological-psychological systems in animals and humans. There is more and more evidence that the proliferation of antibiotic use since the 1940s is implicated in the explosion of Type 1 diabetes, allergies, respiratory disorders, psychological imbalances and inflammatory bowel diseases.

From the standpoint of evolutionary history, the whole concept of an antibiotic is an oxymoron. We cannot live in a microbe free world, nor do we want to: there is nothing living that does. The rhizosphere (the part of the soil that interacts with plant roots) has 100 billion microbial cells per gram root comprising more than 30,000 species. Our microbiome, the bacteria that live in our intestines, on our skin and elsewhere in our bodies, influences our innate immunity, our neurology and our psychology keeping us stronger, happier and wiser. We need to live symbiotically with the 100 trillion or so microbiota populating our body (made up of 10 trillion cells), so how can we preserve health in the face of infections without damaging this critical community that we depend upon?

It appears that the answer is right in front of us. For the past billion years of our multi-celled evolution we have been in a dialogue with the world around us. Our ancestors knew the benefits of the antimicrobial defence mechanisms that plants have developed through their co-evolutionary dance with the environment. Traditional health systems have identified that 50,000 of the 250,000 flowering species in the world have therapeutic properties. These plants still remain effective today. Mankind’s use of these species over millennia suggests that bacteria, fungi and viruses have less ability to develop resistance to a broad botanical pharmacy than to a narrow pharmaceutical one as used in our modern health system. But why is this and how do the herbs work?


Plants contain hundreds to thousands of plant chemicals that carry particular properties that have evolved to protect the static plant from ever-evolving microbial and environmental challenges. Essential oils, aromatic terpenes and colourful flavonoids optimise interaction with the environment enhancing the survival of the plant. Humans and animals have receptors and enzyme pathways that can harness these compounds for our benefit, which points to a positive path ahead for our future healthcare. This is the wonder of synergy as the multiple compounds work together at pharmacodynamic (what the drug does to the body) and pharmacokinetic (what the body does to the drug) levels. These multi-dimensional synergistic effects of plants optimise the chances of efficacy and reduce the likelihood of resistance via multiple mechanisms. So how do herbs work in the face of infection?

Herbs can destroy the microbial cell wall

Essential oil compounds, such as carvacrol and thymol (the hot and spicy compound found in oregano and thyme), destroy the bacterial cell membrane rendering them inactive. Green tea also does this.

Herbs can inhibit bacterial defence systems

Epigallocatechin gallate (EGCG), a polyphenol in green tea, impedes the bacteria’s own enzymes that are released to deactivate antibiotic activity. Tannins also do this and Triphala, one of Ayurveda’s most famous formulas made from the fruits of amla, bibhitaki and haritaki, is often used in antimicrobial formulas.

Herbs can disarm bacteria’s antibiotic rejection system

This system, called the efflux pump, is designed to pump out antibiotics once they’ve entered the bacterial cell and is a major cause of drug resistance. Certain compounds in some herbs inhibit this pump, allowing the antibiotics to deactivate the microbe. Baicalen, found in thyme and some Scutellaria species reverses MRSA resistance to ciprofloxacin by inhibiting the bacteria’s efflux pump.

Herbs can inhibit quorum sensing

Quorum sensing is the bacteria’s own protective mechanism enabling it to rally against compounds that are toxic to it, for example, by creating defensive-matrix biofilms, that act as a inhibitory barriers. Cinnamon, cranberry, garlic, ginseng and propolis interfere with this process, breaking down the web and preventing the microbes adhering together as a powerful conglomerate.

Herbs can initiate mitochondrial disruption in the bacteria

Herbs such as clove, dill and tea tree oil interfere with microbial energy cycles thus weakening its life cycle and rendering the microbe useless.

Herbs can inhibit viral replication

By targeting viral proteins, herbs can disrupt the life cycle of the microbe and block the proliferation of the invading virus. Andrographis has been shown to do this with the cold sores caused by herpes simplex 1 as well as with various flu viruses. Elderberry has been shown to deactivate the neuraminidase enzyme released by eight strains of flu.

Herbs work independently to limit microbial advance as well as enhancing the effects of antibiotics when they are most needed. They work synergistically as a single plant and when used in multi-herb combinations. They also work collaboratively with pharmaceutical antibiotics. As healthcare professionals face the daily onslaught of sore throats, sinus problems, urinary infections and superficial wounds, it begs the question of why we are so readily using antibiotics known to cause resistance when the history, tradition and science for using plants is so robust? This question is particularly urgent given that the big antibiotic guns are being disempowered by overuse rather than preserved for life-threatening situations.


The list of medicinal plants that can enhance immunity and protect from infection is extensive. Further to the above-mentioned species, some of the most favoured in modern herbal clinical practice, also available for over the counter (OTC) use and with solid scientific backing, are andrographis (Andrographis paniculata), echinacea (Echinacea purpurea/angustifolia), elderberry (Sambucus nigra), neem (Azadirachta indica) and tulsi (Ocimum sanctum). Their potential for helping solve the current healthcare crisis is enormous.

Here we have only really discussed the way herbs defend against an attack by bacteria, but the herbal paradigm also embraces the concept of strengthening immunity by galvanizing both innate and acquired immunity. Herbalists use immune modulators to treat the broader range of autoimmune, inflammatory and proliferative disorders such as cancer, so prevalent in modern healthcare. Again, the multi-dimensional and synergistic impact of herbs interfaces with our health in the broadest possible sense; herbs help us adapt to our environment and enhance our response to it.

One of the most interesting ways that these plants, with their complex phytochemical components, appear to work is by interfacing with our microbiome in our gut. As many plant compounds are not actually absorbed into the blood stream, it appears that they initiate signalling through our own probiotic bacteria. Signalling is when herbs initiate a response within our probiotic bacteria so that a chain reaction occurs from herb to bacteria to our wider physiology. This is even more of a reason to not unnecessarily disturb our intestinal gut bacteria with antibiotics and keep our microbiome intact by using natural plants to keep us at our best.

For a list of sources for this article, please click here. Sebastian Pole is an Ayurvedic practitioner and co-founder and herbal director of Pukka Herbs. For more information about the wonders of organic herbs, see www.pukkaherbs.com.

Featured image by Tealet, oregano by Follow these instructions, elderberry by Richard Griffin

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