Hear me out.

Ivermectin… is a miracle drug. Not for COVID-19.

We did the research. It doesn’t do a whole heck of a lot  against viruses in general or the one that causes COVID-19 in particular, and the  rest of this video will not be about that. What ivermectin does do is kick  parasitic infections to the curb, in a way that’s safe, effective, and cheap.

For a huge number of diseases,  it’s a total wonder drug. Which is why scientists are now trying it  against a disease that's dogged humanity since the Stone Age and killed  up to 300 million people in the twentieth century alone. Our best anti-parasitic drug is  stepping into the ring against malaria.

So as the starting bell rings, let’s see  who has the better odds in this fight. [♪ INTRO] Ivermectin has a proven track  record against parasites. When it was discovered, it was revolutionary. That’s because it was the first drug  to earn the fancy title of endectocide, which means it can kill parasites that  live both inside and outside of you.

A lot of internal parasites, like  roundworm, hang around in your GI tract, clinging to your intestines  to soak up the nutrients. But they’re no match for ivermectin, which  messes with the worm's nerve function at certain stages of development,  leading to paralysis and death. And parasites that attack you from  the outside, like scabies burrowing into your skin, are also paralyzed  and killed by ivermectin.

So ivermectin is great for treating  a broad range of parasites. But what about a parasite that has  probably killed about a billion people throughout history, and that has  teamed up with another nasty pest? Of course I’m talking about Plasmodium,  which is the causative agent of malaria.

Technically there are four  major species of Plasmodium, but they all cause malaria, and they all  have a sidekick: the Anopheles mosquito. Immature Plasmodia develop inside of mosquitoes, and then the mosquitoes come to  us and they take a blood meal. During the blood meal they break your skin, and Plasmodia inside their  saliva get into your bloodstream.

Then the Plasmodia invade your liver cells  before infecting your red blood cells. After lots of replicating, the Plasmodia  eventually burst free of the red blood cells, causing malaria symptoms like cyclic fever. This disease has resisted treatment for centuries.

And while ivermectin is good,  scientists wanted to know if it was “kills parasites that fly in on a trojan  horse and hide in your red blood cells” good. So let’s start with the  bigger guys, the mosquitoes. Lab data shows that when people  have ivermectin in their systems during a blood meal, mosquitoes who bite them die much quicker than when they bite untreated folks.

It’s basically just poisoning  your blood so that anything that bites you will eventually  drop dead...which is Metal. A 2015 study found that two days after a  meal, only around 52% of the mosquitoes were still alive, compared to over  97% on the ivermectin-free blood diet. Plus, it completely stopped them from laying eggs.

That means mosquitoes reproduce  less and they die faster, and since Plasmodium needs  mosquitoes to infect humans, that could theoretically mean  fewer malaria infections. But it would be really stellar if ivermectin directly harmed Plasmodium… which it does! Ivermectin messes with the  parasite’s ability to move stuff in and out of its cells,  leading to parasite death.

Beyond that, Plasmodium can  reproduce sexually and asexually, and some studies have found that  both are inhibited by ivermectin. Now other studies haven’t found  the same anti-malaria effect. But with some evidence of ivermectin  harming mosquitoes and Plasmodium parasites alike, there’s buzz about using  it for a mass drug administration, or MDA.

MDA is when a drug is given to  everyone in a geographic area regardless of their disease status in  order to help prevent or treat infection. Now that might sound pretty extreme,  but it can be a super useful tool in health emergencies like the  Ebola outbreak in West Africa, or in places with high infection rates,  like parasitic worms in tropical areas. There’s no question that we need  new tools to combat malaria, but in order for MDA to be considered, the  drug also has to meet certain criteria.

Safety, convenience, and cost all need  to be factored in when considering MDA. Since ivermectin already  has been used for decades, we know it’s generally safe, barring  overdoses or drug interactions, which MDA protocols would take care to prevent. It’s also convenient, available  as a tablet, and most MDA designs only need three days of ivermectin  administration each month.

And even though its cost can vary, ivermectin  is generally a pretty cheap option. We are, right now, losing ground  in the fight against malaria. Ivermectin ticks all the boxes for MDA, and has the potential to act as a double whammy.

The shortening effect it has  on mosquito lifespans makes it seem like it would be highly effective. One research team estimated  that three doses of ivermectin over three months could reduce  new cases of malaria by 71%, and the general prevalence  of cases by over one third. But before we look into how it’s all  going to happen in the real world, all science needs funding,  so let’s take a quick break.

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The hype over ivermectin as a malaria  treatment is real, and if real world data could replicate that, it would be a major  win in the human versus parasite fight. Unfortunately, in the real world,  the results have been… mixed. So in 2019 and 2020, a phase 3 clinical  trial began that used this exact dosing in seven villages in Burkina Faso, with  seven others acting as controls.

They focused their study on children specifically. And despite those very promising projections, the study found that malaria  incidence did not significantly differ between the ivermectin and control group children, nor did ivermectin treatment decrease  the number of infectious bites. As for mosquitoes, lifespans were  shorter for mosquitoes captured a week after drug administration,  but that did not hold true for those captured three  weeks post administration.

Not very promising results. But to be fair, the study experienced  what you might call a complicating factor. See, a few months into the trial,  the government swept through and gave all the villages new bed nets  slathered in insecticides, probably decreasing the incidence  of malaria in /both/ groups.

Great for the study participants overall. Maybe frustrating though, when  you’re the one trying to do science. Luckily the study wasn’t a total wash.

Malaria can cause low hemoglobin levels, since the parasites rip apart the red blood cells. In the study, children who received  ivermectin had significantly higher hemoglobin levels, which  might signal lower parasite burden. A trial in Gambia that didn’t, uh, face the same challenges as that  other study, fared much better.

It found that ivermectin,  administered in combination with another anti-malaria drug called, uh, this,  significantly reduced malaria prevalence. I’m talking about less than half the  cases compared to the control group. But a different study published  in 2025 showed no difference in the rates compared to just  using that other antimalarial drug.

And a 2021 review concluded that  there was just not enough evidence yet to say whether ivermectin is actually  effective at fighting malaria in humans. Research is ongoing, so we will  have to see how more trials wrap up, but something we do know is that  resistance to ivermectin can develop, making it useless over time. Which is where a drug that kills mosquitoes  even better than ivermectin comes in.

Currently used to treat rare metabolic disorders, nitisinone might be the next  big step in malaria research. This state-of-the-art new mosquito-poisoning  development works by inhibiting an enzyme that mosquitoes need to  actually digest their blood meal, and would be administered in  a similar way to ivermectin. Nitisinone’s anti-mosquito  abilities are newly discovered, but there is a lot of  excitement behind this drug too.

Ivermectin may or may not prove  effective against malaria, but up against a disease that affects  hundreds of millions of people each year, it’s worth trying everything we’ve got. So whether it’s ivermectin, nitisinone,  or something else yet to be discovered, if it can fight malaria then  that’s a major research win. And bonus points if it can kill  those pesky mosquitoes too. [♪ OUTRO]