ABSTRACT
Polymers are widely used to control drug release. Carrageenans are natural poly-
saccharides extracted from red seaweed and they show hydrocolloidal properties. These
natural polysaccharides have only been used since 1945, because a substitute for agar was
needed after the Second World War. For a long time similar to other natural gums it was
difficult to standardize these products since the raw material showed different compo-
sitions in dependence on harvesting (1). Nowadays, these seaweeds can be cultivated and
thus the raw material is much more homogeneous. Only during the last decade more
intensive research on the use of carrageenans in pharmaceutical dosage form develop-
ment has started.
