<unk>  is a Diagnostic Agent that is FDA approved for the diagnosis of coronary artery disease. There is a Black Box Warning for this drug as shown here.  Common adverse reactions include Unintended radiation exposure.
Rubidium Rb 82
Indium oxyquinoline
MMDA 
SeHCAT
Hexavalent chromium
Manganese dioxide
Gallium Citrate Ga 67
Ammonium hexachloroplatinate