Disclosed herein are carborane derivatives of Formula I or Formula V, or a pharmaceutically acceptable salt thereof, for use as neuromuscular blocking agents. The carborane is substituted with two cationic functional groups selected from amines that form ammonium cations, ethers and/or alcohols that form oxonium cations, sulfides and/or thiols that form sulfonium cations, and phosphanes and/or phosphines that form phosphonium cations.