Nursing 102 Medication Administration Complete

Nursing 102 Medication Administration Complete Chapter 1 (Karch Pharmacology Book) – Introduction to Drugs Chapter 2 (Karch Pharmacology Book) – Drugs and the Body Chapter 20 – (Craven, Hirnle and Henshaw) Medication Administration Karch Chapter 1- Introduction to Drugs Glossary of Key Terms adverse effects: Drug effects, sometimes called side effects, that are not the desired therapeutic effects; may be unpleasant or even dangerous brand name: name given to a drug by the pharmaceutical company that developed it; also called a trade name or proprietary name chemical name: name that reflects the chemical structure of a drug drugs: chemicals that are introduced into the body to bring about some sort of change Food and Drug Administration (FDA): federal agency responsible for the regulation and enforcement of drug evaluation and distribution policies generic drugs: drugs sold by their generic name; not brand name or trade name product generic name: the original designation that a drug is given when the drug company that developed it applies for the approval process genetic engineering: process of altering DNA, usually of bacteria, to produce a chemical to be used as a drug orphan drugs: drugs that have been discovered but would not be profitable for a drug company to develop; usually drugs that would treat only a small number of people; these orphans can be adopted by drug companies to develop over-the-counter (OTC) drugs: drugs that are available without a prescription for self-treatment of a variety of complaints; deemed to be safe when used as directed pharmacology: the study of the biological effects of chemicals pharmacotherapeutics: clinical pharmacology—the branch of pharmacology that deals with drugs; chemicals that are used in medicine for the treatment, prevention, and diagnosis of disease in humans phase I study: a pilot study of a potential drug using a small number of selected, usually healthy human volunteers phase II study: a clinical study of a proposed drug by selected physicians using actual patients who have the disorder the drug is designed to treat; patients must provide informed consent phase III study: use of a proposed drug on a wide scale in the clinical setting with patients who have the disease the drug is thought to treat phase IV study: continuous evaluation of a drug after it has been released for marketing preclinical trials: initial trial of a chemical thought to have therapeutic potential; uses laboratory animals, not human subjects teratogenic: having adverse effects on the fetus Introduction to Drugs - The human body works through a complicated series of chemical reactions and processes. -Pharmacology is the study of the biological effects of chemicals. I. Sources of Drugs synthetic. A. Natural Sources 1. Plants -Drugs are chemicals that are introduced into the body to cause some sort of change. -When drugs are administered the body begins a sequence of processes designed to handle the new chemicals. These processes, which involve breaking down and eliminating the drugs, affect the body’s complex series of chemical reactions. In clinical practice, health care providers focus on how chemicals act on people. -Nurses deal with pharmacotherapeutics, or clinical pharmacology, the branch of pharmacology that uses drugs to treat, prevent, and diagnose disease. -Clinical pharmacology addresses two key concerns: the drug’s effects on the body and the body’s response to the drug. -For many reasons, understanding how drugs act on the body to cause changes and applying that knowledge in the clinical setting are important aspects of nursing practice. - Some drug effects are therapeutic, or helpful, but others are undesirable or potentially dangerous. These negative effects are called adverse effects, or side effects, of the drug. (See Chapter 3 for a detailed discussion of adverse effects.) - Drugs are available from varied sources, both natural and - Chemicals that might prove useful as drugs can come from many natural sources, such as plants, animals, or inorganic compounds. To become a drug, a chemical must have a demonstrated therapeutic value or efficacy without severe toxicity or damaging properties. - Plants and plant parts have been used as medicines since prehistoric times. Even today, plants are an important source of chemicals that are developed into drugs. For example, digitalis used to treat cardiac disorders and various opiates used for sedation were originally derived from plants. Table 1.2 Drugs Derived from Plants Plant Product Ricinus communis Seed Oil Castor oil (Neolid) Digitalis purpurea (foxglove) Leaves Dried leaves Digitalis leaf Papaver somniferum (poppy) Unripe capsule Juice Opium (paregoric) Morphine (Roxanol) Codeine Papaverine (Pavabid) 2. Animal Products - Animal products are used to replace human chemicals that fail to be produced because of disease or genetic problems. -Until recently, insulin for treating diabetes was obtained exclusively from the pancreas of cows and pigs. Now genetic engineering—the process of altering DNA—permits scientists to produce human insulin by altering Escherichia coli bacteria, making insulin a better product without some of the impurities that come with animal products. -Thyroid drugs and growth hormone preparations also may be obtained from animal thyroid and hypothalamic tissues. Many of these preparations are now created synthetically, however, and the synthetic preparations are considered to be purer and safer than preparations derived from animals. 3. Inorganic Compounds - Salts of various chemical elements can have therapeutic effects in the human body. -Aluminum, fluoride, iron, and even gold are used to treat various conditions. -The effects of these elements usually were discovered accidentally when a cause–effect relationship was observed Table 1.3 Elements Used for Their Therapeutic Effects Element Therapeutic Use Aluminum Antacid to decrease gastric acidity Management of hyperphosphatemia Prevention of the formation of phosphate urinary stones Fluorine (as fluoride) Prevention of dental cavities Prevention of osteoporosis Gold Treatment of rheumatoid arthritis Iron Treatment of iron deficiency anemia B. Synthetic Sources - Today, many drugs are developed synthetically after chemicals in plants, animals, or the environment have been tested and found to have therapeutic activity. -Scientists use genetic engineering to alter bacteria to produce chemicals that are therapeutic and effective. II. Drug Evaluation A. Preclinical Trials - Other technical advances allow scientists to alter a chemical with proven therapeutic effectiveness to make it better. -Sometimes, a small change in a chemical’s structure can make that chemical more useful as a drug—more potent, more stable, and less toxic. -These technological advances have led to the development of groups of similar drugs, all of which are derived from an original prototype, but each of which has slightly different properties, making a particular drug more desirable in a specific situation. - After a chemical that might have therapeutic value is identified, it must undergo a series of scientific tests to evaluate its actual therapeutic and toxic effects. -This process is tightly controlled by the U.S. Food and Drug Administration (FDA), an agency of the U.S. Department of Health and Human Services that regulates the development and sale of drugs. -FDA-regulated tests are designed to ensure the safety and reliability of any drug approved in this country. -Before receiving final FDA approval to be marketed to the public, drugs must pass through several stages of development. - These include preclinical trials and phase I, II, and III studies. The drugs listed in this book have been through rigorous testing and are approved for sale to the public, either with or without a prescription from a health care provider. - In preclinical trials, chemicals that may have therapeutic value are tested on laboratory animals for two main purposes: (1) to determine whether they have the presumed effects in living tissue and (2) to evaluate any adverse effects -Animal testing is important because unique biological differences can cause very different reactions to the chemical. -These differences can be found only in living organisms, so computer-generated models alone are often inadequate. -At the end of the preclinical trials, some chemicals are discarded for the following reasons: • The chemical lacks therapeutic activity when used with living animals. • The chemical is too toxic to living animals to be worth the risk of developing into a drug. • The chemical is highly teratogenic (causing adverse effects to the fetus). • The safety margins are so small that the chemical would not be useful in the clinical setting. B. Phase I Studies C. Phase II Studies -Some chemicals, however, are found to have therapeutic effects and reasonable safety margins. This means that the chemicals are therapeutic at doses that are reasonably different from doses that cause toxic effects. Such chemicals will pass the preclinical trials and advance to phase I studies. - A phase I study uses human volunteers to test the drugs. -These studies are more tightly controlled than preclinical trials and are performed by specially trained clinical investigators. -The volunteers are fully informed of possible risks and may be paid for their participation. Usually, the volunteers are healthy, young men and often women. -Women of childbearing potential are sometimes not good candidates for phase I studies because the chemicals may exert unknown and harmful effects on a woman’s ova, and too much risk is involved in taking a drug that might destroy or alter the ova. Women do not make new ova after birth. Men produce sperm daily, so there is less potential for complete destruction or alteration of the sperm. -Volunteers who elect to participate in phase I studies have to be informed of the potential risks and must sign a consent form outlining the possible effects. -Investigators in phase I studies scrutinize the drugs being tested for effects in humans. They also look for adverse effects and toxicity. At the end of phase I studies, many chemicals are dropped from the process for the following reasons: • They lack evidence of potential therapeutic effect in humans. • They cause unacceptable adverse effects. • They are highly teratogenic. • They are too toxic. - A phase II study allows clinical investigators to try out the drug in patients who have the disease that the drug is designed to treat. -Patients are told about the possible benefits of the drug and are invited to participate in the study. Those who consent to participate are fully informed about possible risks and are monitored very closely, often at no charge to them, to evaluate the drug’s effects. - Usually, phase II studies are performed at various sites across the country—in hospitals, clinics, and doctors’ offices—and are monitored by representatives of the pharmaceutical company studying the drug. - At the end of phase II studies a drug may be removed from further investigation for the following reasons: • It is less effective than anticipated. • It is too toxic when used with patients. D. Phase III Studies E. FDA Approval F. Phase IV Studies • It produces unacceptable adverse effects. • It has a low benefit-to-risk ratio, meaning that the therapeutic benefit it provides does not outweigh the risk of potential adverse effects that it causes. • It is no more effective than other drugs already on the market, making the cost of continued research and production less attractive to the drug company. - A phase III study involves use of the drug in a vast clinical market. -Prescribers are informed of all the known reactions to the drug and precautions required for its safe use. Prescribers observe patients very closely, monitoring them for any adverse effects. Often, prescribers ask patients to keep journals and record any symptoms they experience. Prescribers then evaluate the reported effects to determine whether they are caused by the disease or by the drug. -This information is collected by the drug company that is developing the drug and is shared with the FDA. -A drug that produces unacceptable adverse effects or unforeseen reactions is usually removed from further study by the drug company. -In some cases the FDA may have to request that a drug be removed from the market. - Drugs that finish phase III studies are evaluated by the FDA, which relies on committees of experts familiar with the specialty area in which the drugs will be used. - Only those drugs that receive FDA committee approval may be marketed. - An approved drug is given a brand name (trade name) by the pharmaceutical company that developed it. -The generic name of a drug is the original designation that the drug was given when the drug company applied for the approval process. - Chemical names are names that reflect the chemical structure of a drug. - After a drug is approved for marketing, it enters a phase of continual evaluation, or phase IV study. -Prescribers are obligated to report to the FDA any untoward or unexpected adverse effects associated with drugs they are using, and the FDA continually evaluates this information. -Some drugs cause unexpected effects that are not seen until wide distribution occurs. Sometimes, those effects are therapeutic. III. Legal Regulation of Drugs - The FDA regulates the development and sale of drugs. Local laws further regulate the distribution and administration of drugs. In most cases, the strictest law is the one that prevails. Table 1.5 Federal Legislation Affecting the Clinical Use of Drugs Year Law Impact Enacted 1906 Pure Food and Drug Prevented the marketing of adulterated drugs; required Act labeling to eliminate false or misleading claims 1938 Federal Food, Drug Mandated tests for drug toxicity and provided means for and Cosmetic Act recall of drugs; established procedures for introducing new drugs; gave FDA the power of enforcement 1951 Durham-Humphrey Tightened control of certain drugs; specified drugs to be Amendment labeled “may not be distributed without a prescription” 1962 Kefauver-Harris Act Tightened control over the quality of drugs; gave FDA regulatory power over the procedure of drug investigations; stated that efficacy as well as safety of drugs had to be established 1970 Controlled Defined drug abuse and classified drugs as to their potential Substances Act for abuse; provided strict controls over the distribution, storage, and use of these drugs 1983 Orphan Drug Act Provided incentives for the development of orphan drugs for treatment of rare diseases A. Safety During Pregnancy - As part of the standards for testing and safety the FDA requires that each new drug be assigned to a pregnancy category -The categories indicate a drug’s potential or actual teratogenic effects, thus offering guidelines for use of that particular drug in pregnancy. -Research into the development of the human fetus, especially the nervous system, has led many health care providers to recommend that no drug should be used during pregnancy because of potential effects on the developing fetus. -In cases in which a drug is needed, it is recommended that the drug of choice be one for which the benefit outweighs the potential risk. - In 2014 the FDA established guidelines that will lead to categories related to the presence of the drug in breast milk, indicating the possibility of effects on a baby who is breastfed. This has been an ongoing issue, with increasing numbers of mothers electing to breastfeed and no clinical studies or accurate information available for many drugs. It will take time to see this information appear in prescribing information. Food and Drug Administration Pregnancy Categories The FDA has established five categories to indicate the potential for a systemically absorbed drug to cause birth defects. The key differentiation among the categories rests on the degree (reliability) of documentation and the risk–benefit ratio. These labels have often been confusing and in December 2014 the FDA passed a new rule which will phase out these categories. In their place the prescribing information will have more information under the section “Use in Specific Populations.” This area will outline the risk of using the drug during pregnancy and lactation with data to support the clinical information and information to help health care providers make prescribing and counseling decisions about the use of these drugs in pregnancy and lactation. This change will occur over time and it is thought that it will provide safer use of drugs in these two groups. While the transition is occurring the following categories will still appear and will eventually be phased out. Category A: Adequate studies in pregnant women have not demonstrated a risk to the fetus in the first trimester of pregnancy, and there is no evidence of risk in later trimesters. Category B: Animal studies have not demonstrated a risk to the fetus but there are no adequate studies in pregnant women, or animal studies have shown an adverse effect, but adequate studies in pregnant women have not demonstrated a risk to the fetus during the first trimester of pregnancy, and there is no evidence of risk in later trimesters. Category C: Animal studies have shown an adverse effect on the fetus but there are no adequate studies in humans; the benefits from the use of the drug in pregnant women may be acceptable despite its potential risks, or there are no animal reproduction studies and no adequate studies in humans. Category D: There is evidence of human fetal risk, but the potential benefits from the use of the drug in pregnant women may be acceptable despite its potential risks. Category X: Studies in animals or humans demonstrate fetal abnormalities or adverse reactions; reports indicate evidence of fetal risk. The risk of use in a pregnant woman clearly outweighs any possible benefit. Regardless of the designated pregnancy category or presumed safety, no drug should be administered during pregnancy unless it is clearly needed. B. Controlled Substances Drug Enforcement Agency Schedules of Controlled Substances C. Generic Drugs D. Orphan Drugs - When a drug receives approval for marketing from the FDA the drug formula is given a time-limited patent, in much the same way as an invention is patented. The length of time for which the patent is good depends on the type of chemical involved. When the patent runs out on a brand-name drug, the drug can be produced by other manufacturers. - Generic drugs are chemicals that are produced by companies involved solely in the manufacturing of drugs. -Many states require that a drug be dispensed in the generic form if one is available. This requirement helps to keep down the cost of drugs and health care. Some prescribers, however, specify that a drug prescription be “dispensed as written” (DAW) (i.e., that the brand name product be used). - Orphan drugs are drugs that have been discovered but are not financially viable and therefore have not been “adopted” by any drug company. - Orphan drugs may be useful in treating a rare disease, or they may have potentially dangerous adverse effects. -Orphan drugs are often abandoned after preclinical trials or phase I studies. -The Orphan Drug Act of 1983 provided tremendous financial incentives to drug companies to adopt these drugs and develop them. These incentives help the drug company put the drug through the rest of the testing process, even though the market for the drug in the long run may be very small (as in the case of a drug to treat a rare neurological disease that affects only a small number of people). E. Over the Counter Drugs - Over-the-counter (OTC) drugs are products that are available without prescription for self-treatment of a variety of complaints. -Some of these agents were approved as prescription drugs but later were found to be very safe and useful for patients without the need of a prescription. - Although OTC drugs have been found to be safe when taken as directed, nurses should consider several problems related to OTC drug use: • Taking these drugs could mask the signs and symptoms of underlying disease, making diagnosis difficult. • Taking these drugs with prescription medications could result in drug interactions and interfere with drug therapy. • Not taking these drugs as directed could result in serious overdoses. -Many patients do not consider OTC drugs to be medications and therefore do not report their use. -Nurses must always include specific questions about OTC drug use when taking a drug history and should provide information in all drug-teaching protocols about avoiding OTC use while taking prescription drugs or checking with the health care provider first if the patient feels a need for one of these drugs. IV. Sources of Drug Information - The fields of pharmacology and drug therapy change so quickly that it is important to have access to sources of information about drug doses, therapeutic and adverse effects, and nursing-related implications. A. Drug Labels B. Package Inserts C. Reference Books D. Journals - Drug labels have specific information that identifies a specific drug. -For example, a drug label identifies the brand and generic names for the drug, the drug dosage, the expiration date, and special drug warnings. Some labels also indicate the route and dose for administration - All drugs come with a package insert prepared by the manufacturer according to strict FDA regulations. The package insert, or full prescribing information, contains all of the chemical and study information that led to the drug’s approval. Package inserts sometimes are difficult to understand and are almost always in very small print, making them difficult to read. E. Internet Information SUMMARY • Drugs are chemicals that are introduced into the body to bring about some sort of change. • Drugs can come from many sources: plants, animals, inorganic elements, and synthetic preparations. • The FDA regulates the development and marketing of drugs to ensure safety and efficacy. • Preclinical trials involve testing of potential drugs on laboratory animals to determine their therapeutic and adverse effects. • Phase I studies test potential drugs on healthy human subjects. • Phase II studies test potential drugs on patients who have the disease the drugs are designed to treat. • Phase III studies test drugs in the clinical setting to determine any unanticipated effects or lack of effectiveness. • FDA pregnancy categories indicate the potential or actual teratogenic effects of a drug. • DEA controlled substance categories indicate the abuse potential and associated regulation of a drug. • Generic drugs are sold under their generic names, not brand names; they may be cheaper but in some situations are not necessarily as safe as brand name drugs. • Orphan drugs are chemicals that have been discovered to have some therapeutic effect but that are not financially advantageous for development into drugs. • OTC drugs are available without prescription for the self-treatment of various complaints. • Information about drugs can be obtained from a variety of sources, including the drug label, reference books, journals, and Internet sites. Chapter 2 – Drugs and the Body Glossary of Key Terms absorption: what happens to a drug from the time it enters the body until it enters the circulating fluid; intravenous administration causes the drug to directly enter the circulating blood, bypassing the many complications of absorption from other routes active transport: the movement of substances across a cell membrane against the concentration gradient; this process requires the use of energy chemotherapeutic agents: synthetic chemicals used to interfere with the functioning of foreign cell populations, causing cell death; this term is frequently used to refer to the drug therapy of neoplasms, but it also refers to drug therapy affecting any foreign cell critical concentration: the concentration a drug must reach in the tissues that respond to the particular drug to cause the desired therapeutic effect distribution: movement of a drug to body tissues; the places where a drug may be distributed depend on the drug’s solubility, perfusion of the area, cardiac output, and binding of the drug to plasma proteins enzyme induction: process by which the presence of a chemical that is biotransformed by a particular enzyme system in the liver causes increased activity of that enzyme system excretion: removal of a drug from the body; primarily occurs in the kidneys, but can also occur through the skin, lungs, bile, or feces first-pass effect: a phenomenon in which drugs given orally are carried directly to the liver after absorption, wher