Licensed drugs have established data about their efficacy, side effects, contraindications and toxicity, which makes expected outcomes more reliable<ref>Merck Veterinary Manual (10th Edition) - [http://www.merckmanuals.com/vet/behavior.html Behaviour]. 2011 The Merck Publishing Group.</ref>. Their use is supported by one or more controlled studies. | Licensed drugs have established data about their efficacy, side effects, contraindications and toxicity, which makes expected outcomes more reliable<ref>Merck Veterinary Manual (10th Edition) - [http://www.merckmanuals.com/vet/behavior.html Behaviour]. 2011 The Merck Publishing Group.</ref>. Their use is supported by one or more controlled studies. |