INTRAMUSCULAR ADMINISTRATION OF SALVARSAN 253 



prepared salvarsan solution transferred from the original cylinder with 

 the glass beads into another empty one, so that when the solution is now 

 poured off into the funnel no glass beads can fall into the latter.) 



8. The infusion is stopped when the funnel empties, thus not making 

 use of the fluid that remains in the rubber tubing; if also this quantity 

 is desired more salt solution can be added to the funnel. 



9. On completion, the needle is removed by a quick motion. 



The infusion should be absolutely painless. If it is not, or if an infiltra- 

 tion beneath the skin forms, the needle should at once be removed and the 

 entire procedure repeated using another vein. 



The dose for adults is 0.6 gm., for children 0.2 to 0.3 gm., and for 

 infants 0.02 to 0.05 to o.i gm. Cachectic or very weak individuals 

 should also receive smaller doses. 



There are numerous modifications in the technique; one may fill the 

 glass funnel with the prepared salvarsan solution right at the beginning 

 but have the rubber tube clamped. The apparatus is fixed high up to a 

 stand. The needle is detached from the rubber tube and inserted into 

 the vein; when a distinct stream of blood escapes, showing that the needle 

 is within the vein, the clamp is removed and the rubber tubing with 

 its escaping salvarsan solution attached to the needle. Or, when the 

 needle is in the vessel one may force some salt solution with a syringe 

 through the needle into the vein and notice whether any infiltration occurs, 

 before the salvarsan solution is allowed to flow. Or, a three directioned 

 stop-cock may be employed with this object. 



There is also apparatus with double funnels, one for salt solution 

 the other for the salvarsan; the two are joined below by their rubber 

 tubings into a single outlet; this allows of the infusion of saline first, to 

 discover whether the vein has been properly punctured. 



The Intramuscular and Subcutaneous Injection. 



These methods of administration have to a great degree been dis- 

 continued on account of the accompanying severe local reaction and pain. 

 It is, also uncertain how much of the salvarsan thus injected is actually 

 absorbed. Simple aqueous (acid) solutions of salvarsan, 10 per cent., 

 alkaline solutions with 5 c.cm. of fluid, neutral emulsions, and oily sus- 

 pensions have been employed. 



To prepare the neutral emulsion, the salvarsan powder, e.g., 0.5 gm. 

 is placed in a sterile porcelain dish and triturated carefully with 3 to 4 

 c.cm. of salt solution. The caustic-soda solution is added drop by drop 

 (7 to 9) until on testing with litmus paper the reaction is exactly neutral. 

 If need be a drop of dilute hydrochloric acid may be used. Salt solution 

 or freshly distilled water is added up to 8 c.cm. 



