Liposomes containing a photosensitive material, which undergoes photodegredation on exposure to U.V. light, is retained within the liposome together with a light absorbing material capable of increasing the photostability of the photosensitive. Methods of preparing pharmaceutical compositions containing these liposomes are provided.

Os liposomes que contêm um material photosensitive, que se submeta ao photodegredation na exposição à luz de U.V., são retidos dentro do liposome junto com um material absorvente claro capaz de aumentar o photostability do photosensitive. Os métodos de preparar as composições pharmaceutical que contêm estes liposomes são fornecidos.