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...
^^^ Diazepam might well be more likely if, indeed, they were available as black and green tablets (which I was unaware of), since it was for many years the standard tranquillizer prescribed for anxiety.
As a child back in the 1960s I often remember being told so and so has had a 'nervous breakdown' which I now assume is a name for a 'mental health issue' .
Mohne is correct, re-googling last night I found it was Librium but didn't bother posting. Librium and Valium were like brother and sister though weren't they?