Question:  A guy in my men’s group seems to be swayed by a video of Dr. Pierre Kory at the U.S. Senate talking about ivermectin last week. I sent him your previous post and this is what he responded (main points copied below). Anyway, do you have anything further to say in regards to the video and study?  Portions of his response: “What caught my attention with Dr. Kory’s testimony is his description of the Brazil study that had just come out. In it, 800 health workers were studied with 400 receiving ivermectin and 400 not. He reported that not one of those receiving the drug contracted the disease while, of those not receiving it, 58% contracted it. He also refers to I believe 30 other studies. While this info is what I’m going on and believing in, everyone, of course, needs to make their own determination. I’m requesting a prescription from my doctor!”

Answer: The evidence we have to date is not strong enough to make sweeping determinations about the effect of ivermectin as treatment or prophylaxis.  The danger of jumping to conclusions too quickly is that it can put individuals and populations at risk of adverse outcomes.  We don’t have enough information to know whether ivermectin works, what dose would be the safest and most effective to prevent/treat COVID-19, and whether there are any serious concerns related to ivermectin’s interactions with other drugs or viruses.  When a medication is used for approved indications, its health risks are generally predictable, but when used for a new indication (off-label), the medication’s health risks and effectiveness are unknown.  If you want to protect yourself, the best thing you can do is to wear your mask, keep your distance, wash your hands, avoid the 3Cs– closed spaces, close-contact settings, crowded places, and get the vaccine when it’s your turn!  Read on for my take on Dr. Kory’s testimony.

I read Dr. Kory’s testimony and didn’t see any data on Brazil.  I also didn’t find anything in my quick search of the peer reviewed literature (pubmed.gov) or on clinicaltrials.gov (search terms: ivermectin, covid19, Brazil).  Regardless, I know that his testimony made a lot of waves and that he presented data from several other studies based on his team’s synthesis of 21 ivermectin studies, all of which he reported “show positive results.”  In my quick review of the published literature, I found several peer-reviewed studies that indicated positive results (a couple of examples here, here) but I also found several peer-reviewed studies that were not positive (links here, here, and here).  I raise this issue not because I have a stake in whether ivermectin is good or bad (I hope it works!), but to highlight that there seems to be some bias in the studies that Dr. Kory included in his synthesis.  Among the studies he does cite, there are methodological limitations that make drawing conclusions like, “I’m requesting a prescription from my doctor!” problematic.  The clinical blog, REBEL-EM, provided a really thorough review of several key ivermectin studies in its post of 12/16, COVID-19 Update: Ivermectin, concluding “Ivermectin is interesting, there is certainly signal to evaluate further, but in our desire to want a treatment option, let’s not continue to do the same thing over and over again, as we saw play out with Hydroxychloroquine.” 

Remember our experience with hydroxychloroquine?  Higher doses were associated with cardiac arrest.  Some studies even indicated that treatment with hydroxychloroquine was associated with worse outcomes among COVID-19 patients, including longer hospital duration and increased risk of death.  Again, jumping to conclusions too quickly can put individuals and populations at risk.  If you want to do something, mask up! And when it’s your turn, get the vaccine!  Finally, if you want to read more, this recent COVID-19 treatment ethics paper is an informative read.