APPENDIX 329 



noted objections are not so marked, although not infre- 

 quently encountered, subsequent pain and induration being 

 the most objectionable. Occasionally the indurated area 

 may undergo liquefactive necrosis, resulting in sinus for- 

 mation. 



Owing to the fact that all the arsenic, detectable in ex- 

 creta, is eliminated in three to six days after intravenous ad- 

 ministration, while it persists for a much longer period fol- 

 lowing intramuscular injection, it has been recommended and 

 is practiced by some clinicians to supplement the intravenous 

 in the course of a week by intramuscular injections. The 

 rationale of this modus operandi is not without reason and is 

 deserving of consideration. It can be explained on the as- 

 sumption that by the intravenous injection the drug is at 

 once conveyed to the remotest parts of the body, where it is 

 needed to destroy the spirochsetse, thus producing a so-called 

 " intensive " action in contradistinction to the " perma- 

 nent " action when the drug is exhibited locally and an intra- 

 muscular depot is established. 



The technic of intramuscular injections is somewhat vari- 

 able. Three solutions have been extensively employed: (1) 

 the alkaline solution, (2) the oily suspension and (3) the 

 neutral suspension. Of these the alkaline solution method 

 is to-day probably most commonly utilized. The preparation 

 of the solution may be similar to that described under Intra- 

 venous Administration, differing only in that for intramus- 

 cular injection the drug is dissolved and injected in 20 c.c. of 

 fluid, one-half the quantity being injected on either side.^ A 

 common procedure for the preparation of the alkaline solu- 



* For the intramuscular injection of neosalvarsan a five per cent, 

 solution is employed, since one gramme of the drug dissolved in twenty- 

 two cubic centimetres of water makes an isotonic solution. Therefore, 

 for each 0.15 gramme of neosalvarsan about three cubic centimetres of 

 freshly distilled water should be added. 



