A radiopaque brachytherapy seed for implantation into a subject includes a biocompatible component, a therapeutically active component including a non-radioactive drug, and a radiopaque marker. The biocompatible component is (a) physically associated with a therapeutically active component and (b) in contact with the radiopaque marker. The brachytherapy seed has a size and shape suitable for passing through the bore of a needle having an interior diameter of less than about 2.7 millimeters (10 gauge).
