One aspect of the invention relates to a hydrogel comprising a polymer comprising a plurality of pendent hydroxyl groups, a crosslinker, and a sclerosing agent. Another aspect of the invention relates to a method for reducing lung volume in a patient comprising the steps of advancing into a region of a patient's lung via said patient's trachea a multi-lumen catheter lumen through a bronchoscope; and co-administering, through the multi-lumen catheter, a first mixture comprising a first amount of a polymer containing a plurality of pendent hydroxyl groups; a second mixture comprising a second amount of a crosslinker; and a third mixture comprising a third amount of a sclerosing agent; thereby forming a hydrogel in said region. In certain embodiments, the compositions and methods described herein are intended for use in the treatment of patients with emphysema of the lung.