Do Animals Self-Medicate? The Science Behind How Animals Heal Themselves

Do animals self medicate? How do they do it? With Dr. Jaap de Roode

What if I told you your dog, a butterfly, or even an ant might know a thing or two about medicine?

It sounds like the premise of a Disney movie written by an evolutionary biologist, but it’s actually a fascinating area of scientific research known as animal self-medication.

In this episode of Causes or Cures, I spoke with evolutionary biologist Dr. Jaap de Roode, author of Doctors by Nature: How Ants, Apes, and Other Animals Heal Themselves, about one of the most fascinating questions in biology: Can animals recognize when they’re sick and intentionally use medicine?

The answer is more nuanced—and much more interesting—than you might expect.

Scientists use the term animal self-medication to describe behaviors in which animals consume or use substances that help reduce disease or parasites. Those substances can include plants, tree resins, minerals, insects, soil, and even toxins. But simply watching an animal eat a particular plant isn’t enough to conclude it’s using medicine. One of the biggest scientific challenges is distinguishing between random behavior and true self-medication. That’s where careful observation, experiments, and years of research become essential.

One of my favorite parts of this conversation was discussing whether animals actually know they’re taking medicine. Do they recognize that they’re sick and intentionally seek out a remedy? Or are these behaviors driven by instinct, evolution, or trial and error? Scientists are still working to answer those questions, but the evidence that some animals change their behavior when infected—and benefit from doing so—is becoming increasingly compelling.

Dr. de Roode shares remarkable examples from across the animal kingdom. From monarch butterflies selecting plants that help protect their offspring from parasites to insects incorporating antimicrobial substances into their nests, nature is full of behaviors that look surprisingly similar to medicine. Some animals even appear to use substances that would otherwise be considered toxic if those substances improve their chances of surviving infection or reducing parasite burdens. It’s a reminder that evolution has been running experiments for millions of years.

Our conversation also explores what humans might learn by paying closer attention to the natural world. Traditional healers have long observed animals when searching for medicinal plants, and modern scientists continue to investigate whether studying animal self-medication could lead to new drugs or therapies. At the same time, Dr. de Roode cautions against romanticizing nature. Not every unusual behavior is medicinal, and “natural” doesn’t automatically mean safe or effective. That’s why rigorous science remains essential.

Beyond the fascinating stories, this research has broader implications for evolutionary biology, host-parasite interactions, conservation, drug discovery, and One Health. It also challenges us to think differently about the animals we share the planet with. If other species are capable of recognizing illness and responding in sophisticated ways, what else might we still have to learn from them?

In this episode, we discuss what inspired Dr. de Roode’s research, how scientists determine whether an animal is truly self-medicating, some of the strangest substances animals use to stay healthy, what traditional healers have learned by observing wildlife, whether studying these behaviors could lead to new medicines, and, of course, the big question: Who is the best doctor in the animal kingdom?

If you enjoy animals, nature, evolutionary biology, infectious diseases, or simply discovering another way the natural world continues to surprise us, I think you’ll really enjoy this conversation.

Tune in here, or click on the embedded podcast above!

The conversation had a funny moment where we talked about empathy for cockroaches:

@dr..eeks I never expected a conversation about animal behavior and animals being their own doctors to include me talking about how I felt empathy for a cockroach. 🪳 One of my favorite moments from my fascinating conversation with author and researcher Dr. Jaap de Roode. Have you ever looked at an animal or insect differently after learning more about it? 💡 🎙️ Full conversation on Causes or Cures #sciencetok #healthtok #animalbehavior #biology ♬ original sound – Dr. EeKS

You can also listen to this one on Youtube: