The group of drugs which in therapeutic nomenclature is included under the head of cardiac stimulants or cardiac tonics—the so-called digitalis group—has not yet, as applied to the treatment of cardiopathic states, been displaced by hydrotherapeutic, aërotherapeutic or mechanical therapeutic measures, efficient as these latter means may be. The great practical, as well as therapeutic interest, attached to this oft-discussed group of drugs is sufficient excuse for their present consideration to which this paper is limited. In this connection the terms tonic and stimulant have acquired a synonymous usage, a custom not strictly to be commended, because, while the principal cardiac stimulants have also tonic properties, and may correctly be so employed, there are certain well-recognized cardiac tonics, such as the iodids, which are not available for stimulant purposes. Again, the chief clinical application of this group of drugs is for the purpose of stimulating an incompetent heart.
PATTON JM. CARDIAC STIMULANTS.. JAMA. 1903;XL(6):355–361. doi:10.1001/jama.1903.92490060009002