How Cannabinoids Affect the Immune System During Infections | Research

The takeaway

The endocannabinoid system plays a role in fighting infections, but cannabis use generally increases susceptibility to infectious diseases by modulating immune responses.

Read this if you use cannabis and want to understand how it might affect your ability to fight infections.

Cannabis use generally increases susceptibility to infections through immune modulation

What the researchers found

This review examined the complex relationship between the endocannabinoid system, cannabis use, and infectious diseases caused by bacteria, viruses, parasites, and fungi.

The overall pattern is that recreational or medicinal cannabis use tends to increase susceptibility to infections because of its impact on immune modulation. Cannabis compounds can suppress certain immune responses that are important for fighting pathogens.

However, the endocannabinoid system itself is involved in immune defense. Some evidence suggests endocannabinoid signaling participates in controlling and eliminating infectious agents including certain bacteria, viruses, and protozoa.

Compounds isolated from Cannabis sativa have also shown direct antimicrobial properties in some laboratory settings. The reviewers noted that research on cannabis and fungal infections remains particularly sparse.

Why it matters

For medical cannabis patients, especially those with compromised immune systems, understanding how cannabinoids interact with infection defense is clinically relevant. The dual nature of the system, with endocannabinoids helping fight infections but exogenous cannabis potentially suppressing immunity, creates a nuanced risk-benefit picture.

The numbers in context

The review covered infections across four pathogen categories: bacteria, viruses, parasites, and fungi, with fungi having the least available research.

How the study worked

Narrative review of existing literature on the endocannabinoid system's role during infections, antimicrobial properties of Cannabis sativa compounds, and associations between marijuana use and infectious disease outcomes.

What this study cannot tell us

Narrative review without systematic methodology. Many of the reviewed studies are preclinical or observational. The review does not distinguish between different cannabis preparations, doses, or routes of administration in terms of immune effects.

How to read the evidence

Narrative review synthesizing multiple lines of evidence from preclinical and clinical studies. Moderate because it covers substantial literature but lacks systematic methodology.

When this study was published

Published in 2017.

The bigger picture

This review highlights that the endocannabinoid system evolved partly as an immune regulatory system, not just a neurological one. The immunosuppressive effects of cannabis may be beneficial in autoimmune conditions but harmful during active infections, pointing toward the need for context-specific clinical guidance.

Questions still open

Are medical cannabis patients at measurably higher risk for infections? Could the antimicrobial properties of isolated cannabis compounds be developed into novel antibiotics? Does CBD have different immunomodulatory effects than THC during infections?

Common questions

Does cannabis weaken the immune system?

This review found that cannabis use generally increases susceptibility to infections by modulating immune responses. However, the body's own endocannabinoid system actually participates in fighting infections, so the relationship is complex.

Can cannabis compounds kill bacteria or viruses?

Some compounds isolated from Cannabis sativa have shown antimicrobial properties in laboratory settings. However, this is different from smoking or consuming cannabis, which tends to suppress rather than enhance immune function.

Read the original research

Immunoregulatory Role of Cannabinoids during Infectious Disease.

Neuroimmunomodulation, 24(4-5), 183-199

View on PubMed ↗Publisher’s paper ↗

Citation

Hernández-Cervantes, Rosalía; Méndez-Díaz, Mónica; Prospéro-García, Óscar; Morales-Montor, Jorge. (2017). Immunoregulatory Role of Cannabinoids during Infectious Disease.. Neuroimmunomodulation, 24(4-5), 183-199. https://doi.org/10.1159/000481824