A method for producing foams, such as sponges, from hydrocolloids is described. A solid or semi-solid gel is formed by dissolving polymeric material in an aqueous solvent. The gel formed is allowed to set, and may optionally then be cut into the desired shape. The gel may be frozen to allow formation of ice crystals to act as porogens. Subsequently, the gel is exposed to a radiant energy field for drying under vacuum. This causes the solvent to boil and the foam or sponge is formed. Medicinally active ingredients may be included in the process, so that the sponge or foam formed contains the active ingredient dispersed within the structure. The method described provides an alternative to the conventional methods of particulate leaching or freeze drying.