In the 1940s and 50s, pharmaceutical companies were on the brink of failure. Psychotropic drugs saved them. McGill medical historian Andrea Tone tells how tranquilizers became mainstream - and at what cost - in her fascinating new book, The Age Of Anxiety: A History Of America's Turbulent Affair With Tranquilizers (Basic, $28.95). Sample tidbit: In 1978 alone, nearly 2.3 billion Valium tablets were sold globally, enough to medicate half the world. Geez.