The four essential oils we’ll be looking at have high phenol concentrations (eugenol, thymol, and carvacrol), and while they have strong antimicrobial properties, they can also be dermatoxic, so they should be diluted before coming into contact with the skin.

Three of the strongest oils with a high percentage of carvacrol are oregano, thyme, and cinnamon, however, it is well worth investing in them.

Oregano Essential Oil

It may smell like an Italian salad, but oregano is one of the most potent antibacterial and antiviral essential oils on the planet. Studies have shown that oregano essential oil is effective against 20 different strains of E. coli and pseudomonas aeruginosa, the pathogen known to cause cystic fibrosis.

Oregano oil has also been shown to reduce inflammation in the gut and to aid in digestion. You can dilute it with a cold press carrier oil for topical application. Interestingly, yet not surprisingly, bacterial resistance to standard antibiotics has become a big problem in the health industry. This has brought more attention to plants as possible alternatives to fight bad bacteria.

Studies have shown that oregano oil and silver nanoparticles, also known as colloidal silver, have potent antibacterial activity against some drug-resistant bacterial strains. Results showed that both individual and combined treatments provided a reduction in cell density, which gives way to antimicrobial activity through the disruption of cells. Overall, these results indicate that oregano essential oil can be an alternative in the control of infections.

Cinnamon Essential Oil

Cinnamon essential oil not only has a pleasant fragrance, but studies also confirm that it has activity against Gram-positive bacteria (such as staphylococcus) and Gram-negative bacteria (such as E. coli) responsible for human infectious diseases, as well as bacteria that cause degradation of food or cosmetics.

The cinnamon essential oil has also been proven effective for oral health. Studies published in the Journal of Contemporary Dental Practice were conducted on the effectiveness of cinnamon oil against “planktonic E. faecalis” in a root canal procedure. The results showed that the cinnamon essential oil eliminated bacterial growth after seven and 14 days of the procedure, making it a compatible natural option. The study concluded that “Cinnamomum zeylanicum essential oil is an efficient antibacterial agent against planktonic and biofilm E. faecalis and thus can be a great antimicrobial agent in root canal treatment.

Thyme Essential Oil

Thyme, like oregano, is great as an antimicrobial. Studies were conducted at the University of Tennessee’s Department of Food Science and Technology to evaluate its effectiveness against bacteria found in milk and salmonella. Like with the cinnamon essential oil, droplets of thyme essential oil with the GRAS recognition (generally recognised as safe) were placed on the bacteria.

The findings, which were published in the International Journal of Food Microbiology, suggest that “nano-emulsions” could be excellent options for protecting our bodies from bacteria by using thyme oil as an antimicrobial food preservative. Thyme essential oil is also effective against acne bacteria. Scientific studies show that it is more effective than benzoyl peroxide.

Eucalyptus Radiata

Eucalyptus essential oil has wonderful multi-faceted medicinal properties and the good news is that Australian eucalyptus essential oil is considered to have one of the highest therapeutic constituents in the world. In particular, Eucalyptus Radiata is highly prized for its anti-infectious properties, particularly for respiratory conditions. For this reason, it is found in products such as chest rubs and over-the-counter products for colds and respiratory congestion. Some of the amazing properties of Eucalyptus Radiata include anti-inflammatory, antispasmodic, decongestant, disinfectant, antiseptic and antibacterial.

When used as vapours, the combination of grapefruit seed extract and geranium oil were most effective as antibacterial agents, as was a combination of eucalyptus and tea tree oil. When flying, I always use a high-grade Eucalyptus Radiata oil.


Apply just a few drops to your chest, and also dab it on your nose to protect your breathing, and add a couple of drops on your ear lobes. This is another pathway in the body through which bacteria may choose to enter.

Precautions with Antibacterial Essential Oils

There are many antimicrobial, antibiotic, and antibacterial essential oils that may be hugely beneficial to fighting existing infections, as well as preventing them in the first place. Regardless, essential oils are highly concentrated extracts from plants and need to be used with proper education. Make sure to check with your doctor, and if your doctor does not have any knowledge, find a holistic or functional medicine doctor in your area. It is also important to access your essential oils from a reputable supplier to ensure quality and purity