EFFECTS OF VARIOUS CONDITIONS— IIOMCEOPATHY. 235 



Effect of Habit, Climate, Fasting, and Form of Administration. 

 — The effect of habit in lessening the action of drugs may be 

 due to increased power of excretion or diminished absorption ; 

 and that of a warm climate in increasing the action of narco- 

 tics, such as hyoscyamus, to their excretion being hindered by 

 the diminution in the amount of urine consequent on the 

 increased cutaneous transpiration. A medicine taken by a fast- 

 ing person is generally more rapidly absorbed and has a greater 

 effect than if the stomach be full, as is well known in the case 

 of alcohol. The form of administration has also an effect on the 

 rapidity of absorption. When a drug is given in a soluble foim 

 in small bulk it is more quickly absorbed, and Avill have greater 

 effect than when given in an insoluble form or much diluted. 

 Thus two glasses of raw brandy may intoxicate a man, espe- 

 cially if taken on an empty stomach when the person is thirsty 

 and absorption therefore rapid. The same quantity diluted 

 with two quarts of w^ater would have little or no effect, for 

 before the stomach could get the whole absorbed, the alcohol 

 W'hicli had first found its way into the blood would have been 

 in great part either excreted or consumed. 



Large and Small Doacs, — The effect produced by a small dose 

 of a drug is sometimes exactly the opposite of that produced by 

 a large one. We cannot say exactly why it is so ; but we very 

 generally find that any substance or any condition, whether it 

 be acid or alkali, heat or electricity, which in moderate amount 

 increases the activity of cells, destroys it when excessive.* 



Homoeopathy. — This opposite action of large and small doses 

 seems to be the basis of truth on wdiich the doctrine of homoeo- 

 pathy has been founded. The irrational practice of giving 

 infinitesimal doses has of course nothing to do with the prin- 

 ciple of homoeopathy — similia similihus curantur : the only 

 requisite is that mentioned by Hippocrates, when he recom- 

 mended mandrake in mania ; viz., that the dose be smaller than 

 would be sufficient to produce in a healthy man symptoms 

 similar to those of the disease. Now in the case of some drugs 

 this may be exactly equivalent to giving a drug which pro- 



* Kiilxne, U titer suchu7ig en iiber Froioplasma und ContractiliLdt^ pp. 49, 31, 

 33, and 43. 



