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Essential Lexicon of Pharmacology

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Essential Lexicon of Pharmacology 1 ESSENTIAL LEXICON OF PHARMACOLOGY Francesco Clementi and Guido Fumagalli using tools and methods of these disciplines to test drugs or By reading this chapter, you will: vice versa employing drugs to investigate cellular and molec- ular processes, and a clinician using drugs to cure patients. • Become familiar with the pharmacological vocabulary THE SOCIAL IMPACT OF PHARMACOLOGY Pharmacology studies drugs and their interactions with Using drugs to treat diseases and conditions has changed living organisms. In a broad sense, a drug is any substance the life of humanity (see Chapter 2). Several factors have that induces functional changes in an organism through contributed to the remarkable improvements in population a chemical or physical action, regardless of whether the health that have occurred over the last century in developed resulting effect is beneficial or detrimental to the health of countries: improved hygienic conditions, more widespread the receiving organism. In a more strict medical sense, a culture of prevention and health, richer and more balanced drug is a substance used in the diagnosis, treatment, or pre- diet, and less physically wearing working conditions. However, vention of diseases or as a component of a medication. such effects on life quality and duration would not have been Thus, the fields of interest in pharmacology are multiple, so significant without the development of drugs and evidence‐ including chemistry, molecular and cellular biology, based approaches to human health care. pathology, clinic, and toxicology. Studying a drug may mean Drugs have contributed to the disappearance of many investigating the chemical properties underlying its biological serious diseases. As an example, consider the number of daily activity, or the way to synthesize or extract it, or its effects on deaths from bacterial pneumonia during winter months in cells, tissues, and organs or on healthy and diseased human general hospitals before World War II as compared to the subjects. Pharmacology bridges basic and clinical research, almost total absence of this disease in current death records. as it provides tools for a rational therapy of known pathol- Drugs have also reduced hospitalization, lowered incidence ogies as well as empirical approaches for diagnosis and cure and gravity of several disease‐induced permanent damages, of obscure diseases (cure ex adjuvantibusCOPYRIGHTED). and allowedMATERIAL to manage many serious and degenerative dis- As Leonardo da Vinci said, “The medical doctor will use eases. The most striking example of the role played by drugs drugs in an appropriate way when he knows what a human in the control of serious diseases is the case of acquired being is, what life and complexion are and what health is.” In immune deficiency syndrome (AIDS): in just a few years, this sense, a pharmacologist is a physiologist, as she/he deals specific antiviral drugs have turned the disease from “plague with substances and methods that modify physiological of the century” to a chronic illness compatible with an almost functions. However, she/he is also a pathologist capable of normal life. Pharmacology has also had an impact on surgery, understanding chemical and molecular causes of pathol- as, for example, H2 histamine receptor antagonists and proton ogies, a biochemist and a molecular and cellular biologist pump inhibitors have almost eliminated gastric and duodenal General and Molecular Pharmacology: Principles of Drug Action, First Edition. Edited by Francesco Clementi and Guido Fumagalli. © 2015 John Wiley & Sons, Inc. Published 2015 by John Wiley & Sons, Inc. 0002273903.indd 3 5/8/2015 8:56:20 AM 4 ESSENTIAL LEXICON OF PHARMACOLOGY ulcers and the need for surgical gastrectomy and antibiotics diagnosis, treatment, or prevention of a disease or as a com- have significantly reduced the number of appendectomies. ponent of a medication. From a regulatory point of view, Drug success has been so impressive to induce part of drug is any substance recognized in the Official National the lay public to believe that there could be a “pill” for every Pharmacopoeia or formulary. Nutrients or food constituents disease or any uncomfortable symptom, causing an exces- are not considered drugs. sive “medicalization” of society and often the inability of From a historical point of view, the terms used to indicate people to accept that not all diseases are treatable and not drugs have undergone numerous conceptual and lexical all patients can be cured. Unfortunately, when such huge changes. In the Middle Ages, the term semplici (simple, expectation on medicine collides with a failure, it may lead from the Latin medicina simplex) was used to indicate to a general distrust and irrational refusal of medical treat- medicinal herbs (cultivated in horto dei semplici, the first ments pushing people toward the so‐called alternative medi- one built in Salerno, Italy), minerals, and substances of cines. Based on the ethical principle that drug usage must be animal origin with supposed therapeutic activity; the term supported by scientific demonstrations of its effectiveness in “drug” was introduced in the eighteenth century to indicate a patients, pharmacology has created strict rules that preclin- mixture of biologically active substances present in vegetal ical and clinical drug investigations (see Chapters 54, 55, or animal organisms or parts of these organisms containing and 56) have to comply with before drugs can be approved these substances (e.g., digitalis was a preparation made from for clinical use. These rules are rigorously applied in drug foxglove Digitalis lanata leaves). The term derives probably development and use but are often ignored by producers from the Dutch word droog that indicated the barrels con- and supporters of “alternative medicines.” This lack of taining plants and dried spices imported from India, from severe preclinical and clinical experimentations implies that which drugs were extracted. “alternative” products and procedures often have not under- gone a careful evaluation of benefits (if any) and risks. In Drug Name Drugs may be indicated by (i) the chemical the best cases, the evidence supporting these practices is name, which identifies the chemical and molecular composi- anecdotal, reported by minor scientific journals often lacking tion; (ii) the generic or official name, meaning the name ☞ serious review procedures (see Supplement E 1.1, “Alternative under which the drug is licensed by the manufacturer and or Nonconventional Therapies”). internationally identified, with the initial in lower case; and Pharmacology has also a social impact. Consider, for (iii) the trade name or proprietary/brand name (patented) example, drugs controlling fertility, emotions, and mental indicating the medicine containing the drug, with the initial and physical performances or drugs affecting the individual’s in large upper case. Two examples: perception of the external world or the social plague of drug addiction. 1. Chemical name, 1‐(1‐methylethylamino)‐3‐(1‐naph- Pharmacological treatment of diseases is a duty for social thyloxy) propan‐2‐ol HCl; generic name, propranolol; health systems; it must be guaranteed to the population but proprietary name, Bedranol, Inderal, InnoPran, Tesnol, it also has costs. This has important implications, both Syprol, and so on positive and negative, for the relationships between drug 2. Chemical name, acetylsalicylic acid; generic name, companies and public health systems. All these scientific, aspirin; proprietary name, Aspirin, Ascriptin, Aspro, economic, ethical aspects make pharmacology a discipline Disprin, and so on with very broad and loosen borders in which technical aspects are associated with equally important ethical issues. Medicinal Preparation Specialty indicates the formula- tion labeled with the trade name under which an active ESSENTIAL LEXICON ingredient is sold. Active ingredients can be prepared in dif- ferent formulations: tablet, syrup, ointment, and so on. The For some of the readers, this book will be the first contact active ingredient is generally associated with inert compo- with pharmacology. For this reason, we include here a list of nents called excipient. The excipient should not alter the the terms that are typical of this discipline and frequently pharmacological properties of the active ingredient, but may found in the text. For a more extended definition of each term, modify its pharmacokinetics. The preparation can be carried the reader should refer to individual chapters of the volume. out on an industrial scale, according to the Official National Pharmacopoeias or in accordance with standards approved by the competent authorities. In this latter case, it is named Active Substances “medicinal preparation” or “pharmaceutical specialty.” When Drugs A drug is any substance that induces functional the patient needs an individual drug preparation, this can be changes in an organism by chemical or physical action. In prepared by the pharmacist, a compounding pharmacist in a biomedical context, a drug is a substance used in the the United States. 0002273903.indd 4 5/8/2015 8:56:20 AM ESSENTIAL LEXICON 5 Generic Drugs It is a drug/substance whose patent is Homeopathic Remedies Homeopathy has been proposed expired (usually 15–20 years after its approval). A generic by German physician C.F. Hahnemann in the early nineteenth drug is subjected to simplified authorization procedures by century on the basis of a philosophical interpretation of nature
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