Several U.S. veterinary schools now offer acupuncture training, and more than 4,000 veterinarians are willing to stick lots of tiny needles into your animal in exchange for money. Animal acupuncture is a scientifically dubious practice, and it’s unfortunate that so many vets are willing to perform it without a sound basis in evidence.
If you’re an acupuncture enthusiast, you’re probably getting ready to point me toward studies proving the efficacy of veterinary acupuncture. Before you do that, let’s make a deal: I will concede that there are studies supporting veterinary acupuncture if you concede that there are studies opposing it. The issue is assessing the quality of the studies and determining where the weight of the evidence lies.
Four out of five studies on animal acupuncture are unreliable, and the fifth usually debunks the practice. A 2006 systematic review collected 31 animal acupuncture studies and ranked their methodology on a five-point scale. Two studies earned four points, one earned three points, and two earned two points – and none of those studies found any benefit to acupuncture. The remaining 26 studies scored either zero points or one point, and their methodological flaws should be obvious to any layperson.
Many of them failed to randomly assign animals to groups that received therapy or did not. Others neglected to blind the evaluators to which animals received treatment and which were controls. The studies that included house pets failed to blind the owners, opening the door to the transferred placebo effect – an owner who thinks his dog has been treated is more likely to say that the dog’s health has improved. In 2010, reviewers looking at the broader category of complementary and alternative veterinary medicine wrote that “the available evidence of [complementary and alternative medicine] in veterinary medicine is weak.”
There is confusion in the literature about how exactly to conduct veterinary acupuncture. Some practitioners, for example, discuss the gall bladder meridian in horses, even though horses don’t have gall bladders. In many studies, acupuncturists send electrical pulses through the needles, which massively complicates the interpretation of the results.
“The idea that you can pump electricity into the body and interfere with the perception of pain has been known since the 1800s,” says David Ramey, an equine veterinarian who worked on the American Veterinary Medicine Association’s guidelines on complementary and alternative therapies. “But are we talking about acupuncture or electricity?”
Some of the reviews that support animal acupuncture border on outright dishonesty.
Two years ago, University of Florida veterinarian Huisheng Xie wrote, “An ever-expanding body of evidence-based research supports acupuncture as a clinically useful modality.” Xie styled his collection of studies as a wide-ranging review paper, but he failed to acknowledge the dozens of studies showing that acupuncture does not work. Researchers who write narrative reviews have some flexibility in which studies they choose to include, but to brush aside every study that contradicts your own viewpoint is the professional equivalent of sticking your fingers in your ears and shouting.
Xie’s overzealous support of acupuncture is well-known among veterinarians. “He doesn’t make the effort to use science to control for his tendency to see what he wants to see,” says Brennan McKenzie, president of the Evidence-Based Veterinary Medicine Association and author of the SkeptVet blog.
Xie also has a financial stake in the popularity of animal acupuncture. He founded the Chi Institute of Traditional Chinese Veterinary Medicine, where veterinarians can be certified in acupuncture online or on-site, for $695 or $1350, respectively.
Who cares if someone wants to stick needles in their German shepherd? Fair question.
“Animal acupuncture perpetuates a fraud,” says Ramey. “It also dumbs down the practice of veterinary medicine and allows people to promote their nonsense at the expense of others.”
There is a debate to be had about the ethics of placebo treatments in human medicine, especially when it comes to pain. If a treatment makes you feel better, in some cases that’s just as good as actual improvement. Animals, however, don’t experience the placebo effect. They don’t know why we’re sticking them with needles or stuffing ground-up herbs down their throats. Those things only make you feel better. That’s not why you go to the vet.
Brian Palmer is Slate’s chief explainer. He also writes How and Why and Ecologic for The Washington Post. Email him at firstname.lastname@example.org.