This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
Gentiana, Gentian, is probably the most reliable simple bitter; possessing valuable tonic properties, it stimulates appetite and digestion and relieves atonic conditions unattended with pyrexia. F.e., 5 to 30 I.; compound tincture, 30 I. to 2 K. The citro-chloride and the pyrophosphate of iron are frequently combined with it in the form of an elixir or a syrup.