ABSTRACT
A pharmaceutical dosage form is the entity that is administered to patients so that they receive an effective dose of a drug. Many drug substances can exist in more than one crystalline form, with different lattice arrangements. This property is termed polymorphism. Molecular size and volume have important implications for drug absorption. Drug solubility can also be enhanced by altering its structure; this is one basis for the use of prodrugs. A prodrug is a drug that is therapeutically inactive when administered but becomes activated in the body by chemical or enzymatic processing. Partition coefficient can be used for drug extraction from plants or biologic fluids, drug absorption from dosage forms, and recovery of antibiotics from fermentation broth. The chemical and physical stability of a drug substance alone and when combined with formulation components is critical to preparing a successful pharmaceutical product.
