A process for producing a sterile foam for medical or veterinary use is provided. A physiologically acceptable formulation for application to a body as a foam contains a foamable gelling agent. The formulation is foamed and treated with a precipitant which is calcium citrate or a calcium ion. The precipitant is combined with the foamable gelling agent before or during the foaming of the gelling agent. The foam thus obtained is allowed to cure and is then immersed in a bath of the precipitant. The treated foam is dried and sterilized by exposure to gamma-irradiation or ethylene oxide.