From Nachtrage Über Coca, Verlag Von Moritz Perles, Wien, 1885

3. The Internal Application of Cocaine

As, at present, many authorities seem to harbor unjustified fears with regard to the internal use of cocaine, it is not out of place to stress that even subcutaneous injections – such as I have used with success in cases of long standing sciatica – are quite harmless. For humans the toxic dose is very high, and there seems to be no lethal dose.

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However, the present still artificially high price of the drug is an obstacle to all further experiments.

From ‘Ueber die Allgemeinwirkung des Cocaïnes,’ in Medicinisch-chirurgisches Centralblatt, 32 pp. 374–375. Lecture, August 1885

In my paper "On Coca" (Heitler’s Centralblatt für die gesammte Therapie, July 1884; printed separately by Merits Perles, 1885), I have given several examples of the disappearance of legitimate fatigue and hunger, etc., which I observed largely among colleagues who had taken cocaine at my request. Since that time, I have made many similar observations, among them that of a writer who for weeks before had been incapable of any literary production and who was able to work for 14 hours without interruption after taking 0.1g of cocaine hydrochloride.

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On the whole, it must be said that the value of cocaine in psychiatric practice remains to be demonstrated, and it will probably be worthwhile to make a thorough trial as soon as the currently exorbitant price of the drug becomes more reasonable.

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I myself have had occasion to observe a case of rapid withdrawal from morphine under cocaine treatment here, and I saw that a person who had presented the most severe manifestations of collapse at the time of an earlier withdrawal now remained able, with the aid of cocaine, to work and to stay out of bed, and was reminded of his abstinence only by his shivering, diarrhea, and occasionally recurring craving for morphine. He took about 0.40g of cocaine per day, and by the end of 20 days the morphine abstinence was overcome. No cocaine habituation set in; on the contrary, an increasing antipathy to the use of cocaine was unmistakably evident. On the basis of my experiences with the effects of cocaine, I have no hesitation in recommending the administration of cocaine for such withdrawal cures in subcutaneous injections of 0.03–0.05g per dose, without any fear of increasing the dose.