Could CBD be effective in the treatment of viral diseases?

Translated from Canex site

The main components of the Cannabis plant are known as cannabinoids. It has been found that these compounds interact with receptors in our body, which are responsible for a large number of bodily functions and immune responses. This system is known as the Endocannabinoid System, and the two most prevalent cannabinoids found in the Cannabis plant are CBD (cannabidiol) and THC.

CBD has shown to have some benefits for patients in various conditions, including epilepsy and pain. Furthermore, attention around the therapeutic potential of the compound has also been increasing, however, the evidence in this area remains quite limited. The effect of CBD on viral infections is one of those areas that requires further research to be better understood.

A recent systematic review published by scientists from the UK and Italy evaluated the currently available evidence. The evidence on CBD in viral diseases was considered and compared with claims made on the Internet.

What is the current evidence?

Studies were evaluated for relevance based on the inclusion of the search terms 'CBD' and 'viral' or 'virus'. After evaluating relevant studies, researchers excluded reviews, duplicates, and studies of synthetic analogs, enriched extracts, or CBD metabolites. Three studies were identified as relevant for review.

CBD and Hepatitis C Virus

One study evaluated the effects of CBD on Hepatitis C Virus (HCV) and Hepatitis B Virus (HBV). The virus was assessed in a culture over several days. It was found that CBD was able to inhibit HCV cell replication by up to 86.4%. These results were comparable to interferon alfa (IFN-α) - a therapeutic medication currently used for hepatitis infections.

Additionally, CBD was also less cytotoxic (toxic to cells) than interferon alfa. However, when compared to sofosbuvir, a medication for Hepatitis C treatment, CBD was less effective and more cytotoxic. CBD also did not show a significant effect on the progression of Hepatitis B Virus (HBV).

CBD and Kaposi's Sarcoma-Associated Herpesvirus

Another study evaluated the effect of CBD on Kaposi's Sarcoma-Associated Herpesvirus (KSHV). Researchers used human dermal microvascular endothelial cells (HMVECs) to assess KSHV progression after CBD treatment. The study showed that CBD had some indirect antiviral effects on KSHV.

Although CBD did not affect the efficiency with which KSHV infected cells, it appeared to reduce the spread of KSHV-infected cells. CBD also restricted the development of KSHV-associated cancers in normal cells.

CBD and Theiler's Murine Encephalomyelitis Virus

The final study evaluated by researchers analyzed CBD in the effects of Theiler's Murine Encephalomyelitis Virus (TMEV)-induced neuroinflammation in mice. It was found that prolonged exposure to CBD was able to decrease white blood cell infiltration and microglia activation in the brains of TMEV-infected mice.

As a result, CBD was able to improve motor symptoms and neuroinflammation in the chronic phase of TMEV infection. Although this study demonstrated that CBD has the potential to limit the impact of the chronic phase of the disease, restore motor function, and reverse neuroinflammation, it did not provide any experimental evidence of the direct or indirect antiviral effect of CBD.

Internet Review

Researchers also sought anecdotal evidence from patients on the internet. After analyzing potentially relevant websites, 25 sources were considered applicable to this research. Within these sources, CBD was described as beneficial in viral infections such as oral and genital herpes, common respiratory viruses, shingles, Hepatitis C, HIV/AIDS, Ebola, and glandular fever.

Most of these references were found on commercial websites, educational platforms, and online media. Although a large number of claims have been made about the benefits of CBD for viral infections, few of these sources were supported by appropriate scientific research.

Researchers' Conclusions

Researchers concluded that CBD could be considered a new candidate targeted for the treatment of Hepatitis C and Kaposi's Sarcoma. Furthermore, this review supports the use of CBD as an anti-inflammatory treatment for the deleterious effects of neuroinflammation in TMEV-infected mice.

Although anecdotal evidence may suggest the potential of CBD to benefit some other viral diseases, acceptable evidence is lacking. Researchers conclude that many of these claims were biased interpretations of current evidence and even dishonest manipulation by commercial retailers.

In conclusion, the review authors emphasize that current findings and anecdotal evidence should be used to progress research into its applications in viral diseases and not as appropriate treatment based on the currently limited evidence available.