Basic Concepts and Requirements of Galenic Formulations

Patient acceptance and specific requirements of the active ingredient should be considered in the development of a suitable form of administration. Inactive ingredients (excipients) which can make up most of a medicine’s volume, help carry the active substance in the body. Maize starch or lactose, for example, are used in tablets, while water-oil emulsions are used in ointments.

The administration form also influences how the active substance is absorbed and how available it is. It is therefore important for the medicine’s therapeutic effect. It also determines how the active ingredient enters the body, where and in what dosage it is released, and the time it takes to be absorbed. In addition, the mode of administration must ensure that the patient or health care professional (e.g. doctor or nurse)will be able to dose the medicine safely and handle it easily.

Formulation scientists ensure that the substance can be absorbed by the body and that the therapeutic dose reaches the organ it is meant for (the target organ). Not every active substance is suited to be given as a tablet, and special demands on the form of administration regularly create new challenges for formulation scientists. Examples are injection into the eye, products for inhalation, or orodispersible tablets (tablets that dissolve quickly in the patient's mouth). Innovative pharmaceutical technologies often come into play in this context. Some examples follow.