References

Blanpied TA, Clarke RJ, Johnson JW. Amantadine inhibits NMDA receptors by accelerating channel closure during channel block. J Neurosci. 2005; 25:(13)3312-3322 https://doi.org/10.1523/JNEUROSCI.4262-04.2005

Dale HH. The action of certain esters and ethers of Choline, and their relation to Muscarine. J Pharmacol Exper Ther. 1914; 6:(2)147-190

Lobanovska M, Pilla G. Penicillin's Discovery and Antibiotic Resistance: Lessons for the Future?. Yale J Biol Med. 2017; 90:(1)135-145

Loewi O. Über humorale übertragbarkeit der Herznervenwirkung. Pflüger's Archiv für die gesamte Physiologie des Menschen und der Tiere. 1921; 189:(1)239-242 https://doi.org/10.1007/BF01738910

Mccann G. Pharmacological treatment of significant cardiac arrhythmias. Br J Sports Med. 2000; 34:(5)401-402 https://doi.org/10.1136/bjsm.34.5.401

Peng L, Gu L, Li B, Hertz L. Fluoxetine and all other SSRIs are 5-HT2B agonists - importance for their therapeutic effects. Curr Neuropharmacol. 2014; 12:(4)365-379 https://doi.org/10.2174/1570159X12666140828221720

Sever R, Glass CK. Signaling by nuclear receptors. Cold Spring Harbor perspectives in biology. 2013; 5:(3) https://doi.org/10.1101/cshperspect.a016709

Tatsumi M, Groshan K, Blakely RD, Richelson E. Pharmacological profile of antidepressants and related compounds at human monoamine transporters. Eur J Pharmacol. 1997; 340:(2)249-258 https://doi.org/10.1016/S0014-2999(97)01393-9

Zhao J, Deng Y, Jiang Z, Qing H. G protein-coupled receptors (GPCRs) in Alzheimer's disease: a focus on BACE1 related GPCRs. Frontiers Aging Neurosci. 2016; 8 https://doi.org/10.3389/fnagi.2016.00058

Prescribing for paramedics: pharmacodynamics

02 March 2021
Volume 13 · Issue 3

Abstract

In continuing the Prescribing Paramedic series, this article explores the nature of drug actions that occur within the body. An understanding of these principles allows the paramedic to make an informed decision on the medicines that may be offered, the likely outcomes and possible risks. Often considered a complex subject, this article aims to present a set of principles that the reader can apply to almost all drugs that one may encounter. Where appropriate, relevant case studies have been included to support theory and provide contextual examples.

Understanding the nature of drug actions that can occur in the body allows the paramedic to make informed decisions regarding medicines that may be offered, the likely outcomes and any possible risks. Despite often being considered a complex subject, this article presents a set of principles that are applicable to almost all drugs along with relevant case studies to support theory and provide context where appropriate.

Many drugs exert their effect on the body via an action on cells. The net effect of this can be to:

Drugs can do this in a number of ways, but the most common methods are to chemically bind to the surface of a cell or, in the case of steroids, simply pass through the cell wall. Before discussing these methods in detail, we must acknowledge that these processes occur naturally in the body; our pharmacological interventions simply mimic the endogenous neurotransmitter or hormone. The importance of these endogenous chemicals cannot be understated. Indeed, before acetylcholine was the first neurotransmitter to be identified (Dale, 1914), synapses were widely considered to occur via an electrical process. The matter was largely put to rest after Loewi (1921) carried out his well known frog experiment which initially came to him in a dream. He stimulated the heart of a frog with electrical impulses and had it pump a small amount of nutrient solution. When the fluid was transferred to another heart, it operated similarly, proving that chemical substances convey nerve signals to organs.

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