Librium was a popular drug in the 50's 60s for anxiety and tension ( mainly women ;-)) Probably the most popular prescription written.
It is an anxiolytic agent..........used for anxiety.
However....anxiety may play a part in bipolar ( not my field) and if so Valium is preferred to Librium.
Also for "nervous stomachs" it was combined with an antacid and the drug was called Libraxin.......neither used now.