journal (german)
texts (english)
Home - Medicine and Medical History - Joe and the “Horse Dewormer”

Joe and the “Horse Dewormer”

Science is fun and science is hard. Science stops being fun, when it is used to make a (sometimes even valid) point, by falsifying the evidence and bending the truth.

And thus is the case with Joe Rogan and Ivermectin.

Media doesn’t like Joe. That’s understandable, not just since his own “aww-shucks”-y “I am just a comedian” onslaught of unscientific and provably false claims about COVID-19, SARS-CoV-2, and associated vaccines.

When Rogan got sick with COVID-19 following an infection with SARS-CoV-2, that very same media celebrated. Which in and by itself is pretty disgusting. When he recovered, media had to find a new angle. And that angle was his use of an unapproved, untested, and probably not very effective drug called Ivermectin.

What is Ivermectin?

Ivermectin is a glutamate-gated chloride channel blocker[1]. That sounds pretty fancy but means in essence, that it clogs pores in nerve and muscle cells of invertebrates. Mammals do not have those channels, so it’s pretty safe in therapeutic doses. When it blocks such a channel, though, it prevents a very fundamental part of how nerves and muscles conduct signals from happening.

It was discovered in the mid-70s and has since been clinically tested and approved for a number of parasitic infections in humans and animals. Because parasites are the number one killer in developing nations, this discovery earned the inventors the Nobel Prize in Medicine in 2015.

It can be used as as a horse dewormer, and has been extensively tested, in labs and clinically, and approved for this use. It’s also approved in humans in a number of parasitic infections.

What’s the problem, then?

Ivermectin was falsely claimed to be effective against the development of COVID-19 in persons infected with SARS-CoV-2 (Garegnani, Madrid, and Meza 2021[2]). It bears repeating, since its proponents generally confuse this, that even these false claims did not claim that it eradicated or prevented infections with SARS-CoV-2, but that its mechanism could be used to prevent an infection from developing into COVID-19 by inhibiting cellular replication of the virus.

Evidence for this is spurious. In vitro and in silica (in test tubes, essentially), there seems to have been one batch of eleven, in which an introduced SARS-CoV-2 virus did not replicate as quickly as expected under the addition of Ivermectin. This result could not be replicated (Kim et al. 2020[3]).

Under COVID-19 another curious thing happened. Possibly analogue to online clout, many scientists started to publish faster, less meticulous, research as preprints in an attempt to chase impact point clout. As long as it fit a literature search for COVID-19 or SARS-CoV-2, it led to citations and thus impact points.

When initial preprints about Ivermectin in vitro hit the literature, exactly this happened.

The Rub

Opposition to vaccines is largely based on a perceived lack of clinical studies and uncertainty about unwanted effects and long term effects. These claims are easily debunked, but persist.

Ivermectin, while marketed as an anti-parasitic medication since 1981 and part of the List of Essential Medicines published by the WHO, has never been tested clinically in patients with SARS-CoV-2 infections. Neither efficacy nor long-term effects have been documented.

Back to Joe

And that’s where we come full circle.

In their fervor to disclaim Rogan’s statements about Ivermectin and counter the likely drive towards the drug and away from vaccines by his 32+ million followers and fans, media resorted to calling Ivermectin a “horse dewormer.” While not completely untrue, it does a disservice to the millions of doses given to humans and the true nature of this essential medication.

Arguments against the use of Ivermectin exist. “Horse dewormer” isn’t one of them.

In fact, acts like this create a climate of unscience on either side of a debate, leaving aside the scientists and practitioners who actually work in pandemic response and research. Voices of reason and moderation are squelched in pursuit of absolute truths and a Machiavellian “end hallowing means” approach to communication.

Science, however, is our only way out of this and many other diseases plaguing us today. Arguments like this silence scientific voices and occupy spaces that should be founded in science and open to scientific debate. Just because “they” don’t do it doesn’t mean “we” should sink to their level.

I’m happy Joe made it. I welcome looks across the fence to find more and better means to prevent and treat COVID-19. I disagree with unscientific “savior” claims and equally unscientific name calling.


  1. Wolstenholme AJ. Glutamate-gated chloride channels. J Biol Chem. 2012 Nov 23;287(48):40232-8. doi: 10.1074/jbc.R112.406280. Epub 2012 Oct 4. PMID: 23038250; PMCID: PMC3504739. ↩︎

  2. Garegnani LI, Madrid E, Meza N. Misleading clinical evidence and systematic reviews on ivermectin for COVID-19. BMJ Evid Based Med. 2022 Jun;27(3):156-158. doi: 10.1136/bmjebm-2021-111678. Epub 2021 Apr 22. PMID: 33888547. ↩︎

  3. Kim D, Lee JY, Yang JS, Kim JW, Kim VN, Chang H. The Architecture of SARS-CoV-2 Transcriptome. Cell. 2020 May 14;181(4):914-921.e10. doi: 10.1016/j.cell.2020.04.011. Epub 2020 Apr 23. PMID: 32330414; PMCID: PMC7179501. ↩︎