Australian researchers are suggesting that CBD could be a potent antibiotic, finding in lab tests that the cannabinoid killed all the strains of bacteria, including those that are highly resistant to existing antibiotics, according to a Newsweek report. Moreover, the bacteria did not become resistant to the CBD even after being exposed to it for 20 days – the period when bacteria can become antibiotic-resistant.
The researchers also found CBD to be effective at treating a skin infection in mice.
Mark Blaskovich, the lead researcher on the study and senior research chemist at the Centre for Superbug Solutions, admitted to Newsweek that the team “still don’t know how it works” but CBD “may have a unique mechanism of action given it works against bacteria that have become resistant to other antibiotics, but we still don’t know how.”
“So far, we have only shown it works topically, on the skin surface. To be really useful, it would be good if we could show that it treated systemic infections e.g. pneumonia, or complicated tissue infections, where you have to give it orally or by intravenous dosing. A very preliminary study didn’t show that it works in these more difficult models.” – Blaskovich, to Newsweek
Blaskvich said that the “most challenging part” of the study was getting the permits to handle CBD in their Queensland laboratory. The cannabinoid, he said, is still highly regulated in Australia, despite the fact that the researchers used a synthetic, rather than plant-derived, compound.
Dr. Andrew Edwards, a non-clinical Lecturer in Molecular Microbiology at Imperial College London who was not involved in the research, noted that the Australian researchers only found CBD to be effective for Gram-positive bacteria.
“It is not effective against Gram-negative bacteria, which are especially difficult to develop new antibiotics for because they have a very selective outer-membrane that prevents most drugs from entering the bacterial cell,” he told Newsweek.
Edwards added that, because CBD is “already well-characterized” for human use, if it’s found to be an effective antibiotic, “it could be fast-tracked into clinics.”
The study results were presented at the annual conference of the American Society for Microbiology, ASM Microbe 2019 in San Francisco. They have not been published in a peer-reviewed journal.