Radiopharmaceutical Review Improvement Act of 1996 - Amends the Federal Food, Drug, and Cosmetic Act (FDCA) to require that the safety and effectiveness of a radiopharmaceutical be determined: (1) weighing the probable health benefit against any probable risk of injury or illness; and (2) taking into account the absence or presence of pharmacological and toxicological activity of the radiopharmaceutical and the estimated absorbed dose. Allows the indications for which a radiopharmaceutical intended for diagnostic purposes is approved to refer to processes, processes common to or present in one or more disease states, or a diagnostic procedure used in the diagnosis of one or more diseases. Requires that, if a radiopharmaceutical is the primary mode of action in a combination of drugs, the persons charged with premarket review of radiopharmaceutical products have primary regulatory jurisdiction.