ABSTRACT
This chapter identifies cases in which the use of hard or soft gelatin capsules may be preferred over tablets. It describes the types of formulations that are used in hard versus soft gelatin capsules. The chapter also describes quality control tests for soft and hard gelatin capsules. Hard gelatin capsules often provide formulation capability for uniquely challenging drug molecules. Most of the marketed products contain powders or granules. The liquid- or semisolid-filled hard gelatin capsules have gained popularity. The use of soft gelatin capsule shell imposes significant limitations on the drug formulations that can be encapsulated in this dosage form, that is, restricted to liquids and semisolids. In comparison to soft gelatin capsules, the manufacturing process of hard gelatin capsules is less demanding, tedious, and costly. This is because the soft gelatin capsule manufacture requires the formation of gelatin ribbons during the encapsulation process itself, whereas the hard gelatin capsules use premanufactured capsule shells.
