Could CBD Be An Antibiotic?

The relationship between infection and conventional antibiotics

Could CBD be useful in the fight against resistant strains of bacteria? Findings from the University of Queensland in Australia suggest it could be. But, before we take an in-depth look at the study, it helps to understand the evolving relationship between bacteria and antibiotics.

Since the groundbreaking discovery of penicillin by Alexander Fleming in 1928, antibiotics have been an essential tool in the fight against bacteria and infections. And while we still use the same tried and tested methods today, bacteria have evolved. When exposed to antibiotics, some bacteria, fungi, and parasites are able to adapt and nullify the drug's effectiveness by developing a resistance.

It's worth pointing out that antimicrobial resistance was likely to occur anyway, as the genetic code of bacteria changes over time. However, the overuse of antibiotics is believed to be a significant factor accelerating the development of resistant strains.

According to the World Health Organisation, antimicrobial resistance "is an increasingly serious threat to global public health that requires action across all government sectors and society". This has led researchers off the beaten path as they try to identify compounds that might be useful in supporting the fight against harmful bacteria. One such compound being invoked is cannabidiol (CBD), a cannabinoid found in Cannabis sativa.

Researchers are looking for new ways to tackle infections and resistant bacteria

Dr. Mark Blaskovich, Principal Investigator and Program Coordinator for the Community for Open Antimicrobial Drug Discovery, and Senior Research Officer at the Institute for Molecular Bioscience at The University of Queensland, found CBD to be effective against gram-positive bacteria. Strains of gram-positive bacteria include Staphylococcus aureus (common in skin infections) and Streptococcus pneumoniae (common in bacterial pneumonia).

Dr. Blaskovich presented his findings at an annual meeting for the American Society for Microbiology. In vitro samples of both types of gram-positive bacteria were treated with synthetic CBD. Results led Dr. Blaskovich to the conclusion that CBD performed at similar levels as prescription antibiotics vancomycin and daptomycin. He also found that CBD appeared to work against gram-positive strains of resistant bacteria, something many traditional antibiotics are starting to fail at.

"Notably, activity was retained against resistant strains of Staphylococcus aureus (MRSA, VISA, VRSA), Streptococcus pneumoniae (MDR), and Enterococcus faecalis (VRE). Cannabidiol was bactericidal, showed low levels of propensity to induce resistance, and was active against MRSA biofilms".

The team also conducted another study using topical CBD to treat a skin infection in mice. Again, while the results were positive, CBD did not appear to clear the infection, but merely reduce the number of bacterial cells.

Could CBD become an antibiotic?

While it would be easy to praise this work as a significant breakthrough in the antibacterial capabilities of CBD, it's too early to ditch penicillin just yet.

Although it is believed that CBD's effectiveness may come from the way it attacks the biofilm surrounding bacterial cells, the authors are still unsure of CBD's mechanism of action. They were also quick to point out the study's shortcomings. Dr. Blaskovich highlighted that because the results are in preliminary stages, it is far too early for individuals to start self-treating infections with CBD.

The study was also performed in vitro (outside of the human body), and there's a risk that we wouldn't see the same results in clinical trials. Several compounds have shown antibacterial effectiveness in Petri dishes, but failed at this crucial stage. It is also worth mentioning that both studies were performed in collaboration with Botanix Pharmaceuticals Ltd., a drug company specialising in topical CBD products.

Nevertheless, this research might be a significant step forward for CBD and the fight against antimicrobial resistance. CBD continues to show a good safety profile and is not considered toxic, even in large amounts. Thankfully, Dr. Blaskovich and his team plan to continue their research by testing CBD in animal models of infection. The hope is that they can identify which bacterial strains it might reduce, which it could kill altogether, and the exact mechanism of action.