Percy, Pavlov and placebo in animals
One argument that I hear with unfailing regularity when discussing with CAM enthusiasts is this: “It cannot be a placebo, because animals benefit from homeopathy”. This notion is not just wrong, it is wrong three times over! Let me explain.
One argument that I hear with unfailing regularity when discussing with CAM enthusiasts is this: "It cannot be a placebo, because animals benefit from homeopathy". This notion is not just wrong, it is wrong three times over! Let me explain.
First, who says that a treatment which is effective for animals also works for human patients or vice versa? I once had a girlfriend, who insisted on seeing a vet when she was ill.
I would not generally recommend this behaviour, however. Some treatments might work in an animal but not in humans. Some treatments work in humans but not in animals. Other treatments work in both and others again in neither species.
Second, who says that animals do not benefit from placebo-effects? If I remember correctly, Pavlov discovered conditioning in dogs – and conditioning is clearly part of a placebo response.
My dog, Percy, has a mini-depression each time I travel, and lately he even does so at the mere sight of me carrying a suitcase. No placebo-effects in animals? I am sure this is wrong.
Third, who says that animals benefit from homeopathy? The trial data are, of course, not entirely uniform but their totality fails to show convincingly that homeopathy works in animals.
A recent randomised placebo-controlled, double-blind trial is a case in point. American vets tested whether dogs that panic during fire-works (like my Percy) experience less anxiety after a homeopathic treatment specifically designed for that problem.
The outcome? Well, I think you already know it (The Veterinary Journal 2008;177:80-88).Professor Edzard Ernst, professor of complementary medicine at Peninsula Medical School Recent posts
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