Popular in recent years, CBD (or cannabidiol) is the main chemical compound extracted from the hemp plant. Unlike its isomer THC (tetrahydrocannabinol), it has no psychoactive effects, but it does affect the course of intoxication induced by THC. This is why cannabidiol has been shown to be effective in treating anxiety, pain and inflammation. Several years ago, the U.S. Food and Drug Administration (FDA) approved the first drug made from cannabidiol (CBD) in the U.S. to treat one form of epilepsy.
For several years, researchers have been investigating the utility of CBD as an antibiotic. A collaboration between Australia’s University of Queensland and early drug development company Botanix Pharmaceuticals has shown that cannabidiol can effectively fight a wide range of Gram-negative bacteria, including those that cause gonorrhea (Neisseria gonorrhoeae), meningitis and legionellosis.
The same team of researchers also found that CBD also works very well against Gram-positive bacteria, including bacteria that cause Staphylococcus aureus or the pneumonia distemper, which have developed drug resistance. These bacteria have an extra outer membrane, an additional line of defense that makes it difficult for antibiotics to penetrate them.
The researchers compared the effectiveness of cannabidiol to the currently used antibiotics vancomycin and daptomycin. In some cases, CBD even did better against bacteria because it fought strains that had become resistant to antibiotic drugs. In laboratory experiments, CBD fought bacteria that were difficult to treat: staphylococcus aureus and Streptococcus pneumoniae. CBD has also shown activity against bacterial biofilms, which lead to infections that are difficult to treat.
The team of researchers mimicked two weeks of patient treatment in lab models to see how quickly the bacteria mutated in an attempt to outsmart CBD. Cannabidiol showed a low tendency to induce resistance in bacteria. CBD probably kills bacteria by rupturing their outer cell membranes. However, more research needs to be done to better understand this process. The research team also discovered that chemical analogs – created by slightly altering the molecular structure of CBD – were also active against bacteria.
No new classes of antibiotics for Gram-negative infections have been discovered and approved since the 1960s, and now there is an opportunity to design new CBD analogs with improved properties.
Published data demonstrates the enormous potential of CBD to develop effective treatments for incredibly problematic infections with antibiotic-resistant bacteria. The antibacterial effects of cannabidiol have so far only been tested on mouse tissues. More research will be needed to see if CBD could be used as an antibiotic to treat infections in humans. Current research has already yielded results, but it is at an early stage.