758 
PKOF. H. D. HANSON. 
A very important point which I wish to bring out, and 
which caused me to select digitalis as my subject, is one that I 
find overlooked, not only by the student, but also by prac¬ 
titioners, both of human and veterinary medicine, is that digi¬ 
talis does not stimulate the heart in the same way that ammonia 
and alcohol do, but that, as I have already mentioned, digitalis 
increases the contractile power of the heart muscles, which 
power these muscles retain as long as the drug is given. 
Another point is that the contractions in the arteries often 
remain after digitalis has been discontinued, and on this 
account, obstruction in these vessels remains and interferes with 
the action of the heart. It is claimed that this arterial tension 
can be overcome by combining nitroglycerine with digitalis. 
Nitroglycerine dilates the arteries, the heart beats quickly, the 
contractions are powerful, but it does not interfere with the 
action of digitalis. Strophanthus may also be added, as it in¬ 
creases the power of the heart’s action, but does not raise the 
tension in the arteries by interfering with their calibre. This 
combination is beneficial to overcome a weak heart due to 
arterial obstruction. 
The action of digitalis is often increased by cold and by 
such drugs as ergot, belladonna, etc. 
The preparations of the drug are the powder, abstract, in¬ 
fusion, fluid extract, solid extract and the tincture. 
Of the powder, the horse takes from lo to 40 grains, the dog 
I to 3 grains, the cow 30 to 60 grains. 
The fluid extract of digitalis is probably the best form to 
administer ; the dose for the horse being io to 40 minims, the 
dog I to 3 minims, the cow ^ to i drachm. 
These doses are only approximate, as the so-called symptom 
medicines, of which digitalis is an example, have to be given, 
gradually increasing the dose till the physiological effect is pro¬ 
duced. The dose varies in individual cases and as it is a very 
important point, the fact should not be overlooked in order to 
insure the proper results. 
A very important feature in the administration of drugs is, 
