Introduction: What Are Immunotherapies?
Immunotherapy is a type of cancer treatment that helps your immune system fight cancer. Several types of immunotherapy are used to treat cancer. These treatments can either help the immune system attack the cancer directly or stimulate the immune system in a more general way.
Learn more in the videos, below.
Use of Antibiotics May Reduce the Effectiveness of Immunotherapies

Antibiotics are certainly not contraindicated for those who are on immunotherapies. They are essential in the treatment of bacterial infections, and I want patients to take these if they have this type of infection.
The concern is that many individuals are prescribed antibiotics for conditions that are likely viral in origin. Additionally, Americans consume a significant amount of non-organic animal meat, fish and poultry (which are raised on antibiotics); a known major cause of antibiotic resistant infections in humans.
Multiple studies show that the use of antibiotics during an immunotherapy course is associated with a marked reduction in cancer outcomes in these individuals.
The likely cause of this negative association is the impact of the antibiotics on the gut flora (microbiome), leading to a marked depletion of healthful immunity-supporting, anti-inflammatory organisms.
- https://www.ncbi.nlm.nih.gov/pubmed/29617710/
- https://www.ascopost.com/issues/march-25-2019/antibiotic-treatment-prior-to-immune-checkpoint-inhibitor-therapy/
- https://ascopubs.org/doi/abs/10.1200/JCO.2018.36.15_suppl.3010
Use of Probiotics May Reduce the Effectiveness of Immunotherapies

The reason for why probiotic (supplemental organisms native to the GI tract) use is associated with worse cancer outcomes in those on immunotherapies is not known. It likely is due to overcrowding of the GI tract with too many of 1 or more organisms, offsetting the natural balance.
Ask a functional medicine provider about assay testing that can help better identify the specific organism imbalances that may need to be supplemented. Blindly taking a probiotic supplement without testing doesn’t make much sense.

Lack of Gut Microbiome Diversity May Reduce the Effectiveness of Immunotherapies

Any process that leads to an imbalance of normal organisms in the GI tract can cause local and systemic inflammation (and symptoms throughout the body), malabsorption, leaky gut, hormonal disregulation and immune suppression. Common causes for low diversity and imbalances in the gut microbiome include: stress, lack of quality sleep, inflammatory and highly-processed foods, low fiber diets, physical inactivity, medications and toxic chemicals.
Ask your functional medicine provider about assay testing to find out the status of your gut microbiome, intestinal inflammation and other important variables. We often track the results of these assays over time to make sure the targeted interventions that we recommend are leading to the intended goals.
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6471869/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6482659/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5827966/
A Lower Fiber Diet May Reduce the Effectiveness of Immunotherapies

Low fiber diets are associated with worse cancer outcomes in those on immunotherapies. This is presumably related to the loss of microbiome diversity and imbalance of organisms in the GI tract. Fiber acts as a “prebiotic,” which intestinal organisms use to feed on and naturally flourish.
Chronic Stress May Reduce the Effectiveness of Immunotherapies

Stress hormones (such as cortisol and adrenaline or epinephrine) are known immunosuppressive compounds. Elevated levels of these chemicals are common in individuals who are chronically stressed. Reducing these hormones or their effects through stress reduction activities or drug therapies (i.e. Beta-blockers) may improve outcomes in those on immunotherapies.
Get a functional medicine assay that evaluates your cortisol levels throughout the day. Once you identify if you actually have levels that are above/below the normal range, you can focus on making targeted interventions to help normalize them.
Use of Corticosteroids May Reduce the Effectiveness of Immunotherapies

There are many reasons that your doctor will prescribe corticosteroids.

While there are numerous evidence-based treatments that require these medications, they also can have a downside which is that they can suppress the immune system. Any immune suppressing condition can therefore impair the effectiveness of immuntherapy drugs.