Fifthly, Synergists are drugs having the same pharmacological final 

 effects though the manner of action may be slightly different. For ex- 

 ample, colocynth, aloes and potassium sulphate are synergists, as they are 

 all purgatives. All of these occur in the Compound Pill of Colocynth. It 

 is often an advantage, and this is especially the case in the administration 

 of purgatives to include in a prescription two or more synergists. As in 

 the instance mentioned above, when synergists are administered together 

 it is necessary to give any one drug in only a fraction of its full dose. 



Finally, the pharmacopoeial doses are not enjoined and the practitioner 

 must use his own judgment. In many cases it is quite allowable to ex- 

 ceed the pharmacopceial dose if the effects wished for are not achieved by 

 its administration and the physician should carefully watch each and every 

 patient and convince himself that the drugs given are really producing the 

 wished for action. In other words he must not take it for granted that 

 because he gives a pharmacopceial dose of any drug that he must as a 

 consequence get the described pharmacological action. 



The doses of the pharmacopoeia are usually, and unless otharwise is 

 stated, for administration by the mouth. Many drugs can however 

 with advantage be administered by hypodermic, intramuscular or even by 

 intravenous injection. Owing to the more rapid absorption as a rule of 

 drugs given by these methods and to the certainty that they will be ab- 

 sorbed in their entirety it is not necessary that such large doses be given. In 

 those cases in which drugs have given by intravenous injection only a small 

 fraction of the dose given by the mouth was used. For drugs given sub- 

 cutaneously (hypodermically) about one half of the dose is given that would 

 be used if given by the mouth. Drugs given by inunction must be given 

 in larger doses than would be used if they were given by the mouth. The 

 same is true as a rule for drugs given by the rectum if they are intended to 

 have a general action. 



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