Studies on the Clinical Pharmacology of Sodium Salicylate

Parker, William A (1947) Studies on the Clinical Pharmacology of Sodium Salicylate. MD thesis, University of Glasgow.

Abstract

To complete this thesis, the following brief summary is presented of the conclusions reached in the preceding investigations: CHAPTER I. Although maximum plasma concentrations occur two hours after oral administration of sodium salicylate, four hourly dosage maintains plasma concentrations satisfactorily. The dose can be related to body weight but increases in dosage above 14 grs. per stone body weight give marked increases in plasma concentrations. Sodium bicarbonate administered concurrently reduces plasma levels while Ammonium chloride raises them. Long continued administration of sodium salicylate leads to gradually decreasing plasma concentration of salicylate. The concurrent administration of para-aminobenzoic acid has much the same effect as ammonium chloride in that it raises the plasma salicylate concentration. A low fluid intake will give a marked rise in plasma concentration of salicylate on continued dosage, a factor of considerable interest in children where diminished fluid intake is an early feature of salicylate poisoning, but exercise on the other hand has no effect on the plasma levels of salicylate. Inadequate shaking of bottles containing sodium salicylate - sodium bicarbonate mixtures or long standing of these mixtures, leads to inaccurate dosage with consequent effect on plasma concentrations. In adults the administration of 150 grs. or more of sodium salicylate per day leads to a fall in the alkali reserve which can be readily counteracted by the administration of sodium bicarbonate. At the end of chapter I. the method of estimation of plasma salicylate was briefly described, together with a modification found necessary for the estimation of very small amounts of salicylate in the plasma. CHAPTER II. Rectal absorption of sodium salicylate is slower than with oral administration but adequate plasma levels may be maintained by eight hourly rectal enemata of sodium salicylate alone. The technique of administration is simple and this form of administration is well tolerated with little upset in bowel rhythm. The addition of sodium bicarbonate rectally decreases the absorption of sodium salicylate markedly while if given concurrently by the mouth facilitates elimination of the salicylate. Rheumatic fever cases can be treated throughout by rectal enemata of sodium salicylate as effectively as by oral administration of the drug. CHAPTER III. The plasma concentrations obtained by daily intravenous administration compare unfavourably with those obtained by the administration of the same amount of the drug daily by the mouth. The reduction in alkali reserve is more marked with intravenous injection of the drug and toxic effects more severe. These observations led to the abandonment of the intravenous route as a method of administration of sodium salicylate. CHAPTER IV. The concentration of salicylate in the body fluids is governed by the free salicylate fraction in the plasma which increases relatively but to a greater extent as the total salicylate in the plasma rises. Thus as the total salicylate in the plasma increases there is a proportionately greater increase in the concentration in the body fluids. The concentration in the C. S. F. , however, lags behind the free salicylate of the plasma and requires many days to reach an equilibrium with it, but concentration of salicylate in other fluids is more comparable to the free salicylate in the plasma. (Abstract shortened by ProQuest.).

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Keywords: Medicine, Pharmacology
• Date of Award: 1947
• Depositing User: Enlighten Team
• Unique ID: glathesis:1947-79653
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 31 Mar 2020 09:09
• Last Modified: 31 Mar 2020 09:09
• URI: https://theses.gla.ac.uk/id/eprint/79653