In addition to the non-philatelic references cited at the end of "The Peruna Story" article linked by 1typesetter, there are additional similar books covering other aspects and time periods of patent medicines including:
Another book by James Harvey Young "The Medical Messiahs", for 20th century coverage.
Gerald Carson's "One for a Man, Two for a Horse", which has lots of trade card and ad illustrations.
Lastly, I would mention a hard-to-find 3 volume set published by the American Medical Association titled "Nostrums and Quackery"
vol 1, revised and enlarged edition, published 1912.
vol 2, published 1921.
vol 3, published 1936, with an expanded title of "Nostrums and Quackery and Pseudo-Medicine"
The well-indexed volumes list thousands of patent medicine brands, company names, and proprietors.

As an example relating to Ka-Tar-No, pages 587-589 of volume 1 provide the 1912 list of preparations deemed to be beverages and not medicines. Ka-Tar-No is midway down the first column on page 588.



Pages 690-692 of volume 1 provide additional specific coverage of Ka-Tar-No:


