With the Concordant Materia Medica, Frans Vermeulen set out to create a comprehensive one volume handbook of materia medica, using Boericke's Materia Medica as a starting point. He added symptoms from the following books:
- C. Hering: Guiding Symptoms
- T.F. Allen: A Primer of Materia Medica for Practitioners
- C.M. Boger: A Synoptic Key of the Materia Medica
- A.C. Cowperthwaite: A Text-Book of Materia Medica and Therapeutics
- A. von Lippe: Key Notes & Red Line Symptoms of Materia Medica
- Pulford: Homeopathic Materia Medica of Graphic Drug Pictures and Clinical Comments
- J.H. Clarke: A Dictionary of Practical Materia Medica
- J.T. Kent: Repertory of the Homeopathic Materia Medica
- F. Vermeulen: Synoptic Materia Medica
