The study of biopharmaceutics is based on fundamental scientific principles and experimental methodology. Studies in biopharmaceutics use both in-vitro and in-vivo methods. In-vitro methods are procedures employing test apparatus and equipment without involving laboratory animals or humans. In-vivo methods are more complex studies involving human subjects or laboratory animals. Some of these methods will be discussed in . These methods must be able to assess the impact of the physical and chemical properties of the drug, drug stability, and large-scale production of the drug and drug product on the biologic performance of the drug. Moreover, biopharmaceutics considers the properties of the drug and dosage form in a physiologic environment, the drug's intended therapeutic use, and the route of administration.