Many patients ask me about what supplements they can take to boost their immune systems. One of the most common supplements taken across the world for immune support is concentration of the echinacea plant.
Across the upcoming series of posts on how to boost our immune systems against SARS-CoV-2, I want everyone to know that there have been no supplements specifically validated or tested against COVID-19. Hence, all of the information that we discuss is extrapolation, ideally from other coronavirus strains.
Moving on: is there any evidence for echinacea in preventing or reducing symptoms of infections? We cannot talk about all the available evidence in this post, but suffice to say that while there is evidence, it is confounded by several factors. These are the same factors that confound much of our study of botanical treatments: specific plant species, part of plant used, purity, additives, dose, and extraction method, to name a few. It is important to remember that this represents a fundamental difference between the medications that we doctors typically prescribe, because those medications are highly purified, isolated active compounds.
You may be wondering why we even bother using plant-based medications? While this is a very extensive discussion, the main reason is because, by virtue of not being a single isolated chemical, plant medications provide lower potency side effects distributed across multiple active constituents. I plan on writing post to specifically discuss this topic.
So, back to the evidence for immune system support. In multiple studies, including some higher quality randomized clinical trials, E. angustifolia root specifically has shown modest benefit in preventing and reducing duration of upper respiratory infections. It has few side effects and medication interactions, though, as with any herbal medication, always consult your doctor before starting.
Specifically with regards to COVID-19, no formal, randomized studies have been performed to date. However, there is a theoretical concern: one of the concerning findings in COVID-19 cases is immune system “over reaction” (leading to “cytokine storm”). As an immune system stimulant, echinacea may increase production of particular inflammatory agents (called interleukins), which may explain its effectiveness in preventing and reducing duration of illnesses. However, in the setting of COVID-19, where significant morbidity may result from immune system overstimulation, this may be dangerous.
My recommendation? Echinacea may be safe for generalized prevention, but you should strongly consider discontinuing echinacea products at the first onset of symptoms or in the event of a positive COVID-19 test result.
I look forward to more posts on immune system boosting methods! Stay safe everybody!