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    Glossary Entries
    Word(s) Definition Image Caption Link Source
    Absorption The first stage of pharmacokinetics: medications enter the body and travel from site of administration into the body’s circulation.        
    Adverse Effect An unintended and potentially dangerous pharmacological effect that occurs when a medication is administered correctly.        
    Affinity The strength of binding between drug and receptor.        
    Agonist A drug that binds to a “receptor” and produces an effect.        
    Antagonist A molecule that prevents the action of other molecules, often by competing for a cellular receptor; opposite of agonist.        
    Bioavailability The presence of a drug in the blood stream after it is administered.        
    Blood-Brain Barrier A nearly impenetrable barricade that is built from a tightly woven mesh of capillaries cemented together to protect the brain from potentially dangerous substances such as poisons or viruses.        
    Distribution The second stage of pharmacokinetics; the process by which medication is distributed throughout the body.        
    Dose-Response As the dose of a drug increases, the response should also increase. The slope of the curve is characteristic of the particular drug-receptor interaction.        
    Duration: The length of time that a medication is producing its desired therapeutic effect.        
    Efficacy The maximum effect of which the drug is capable.        
    Excretion The final stage of pharmacokinetics; the process whereby drug byproducts and metabolites are eliminated from the body.        
    First Pass Effect The inactivation of orally or enterally administered drugs in the liver and intestines.        
    Mechanism of Action How a medication works at a cellular level within the body.        
    Metabolism The breakdown of a drug molecule via enzymes in the liver (primarily) or intestines (secondarily).        
    Onset When a medication first begins to work and exerts a therapeutic effect.        
    Peak When the maximum concentration of a drug is in the bloodstream.        
    Pharmacodynamics The study of how drugs act at target sites of action in the body.        
    Pharmacogenetics The study of how a person’s genetic make-up affects their response to medicines.        
    Pharmacokinetics The study of how the body absorbs, distributes, metabolizes, and eliminates drugs.        
    Pharmacology The science dealing with actions of drugs on the body.        
    Pharmacy The science of the preparation of drugs.        
    Potency The drug dose required to produce a specific intensity of effect.        
    Selectivity A “selective” drug binds to a primary and predictable site creating one desired effect. A “non-selective” drug can bind to many different and unpredictable receptor sites with potential side effects.        
    Side Effect Effect of a drug, other than the desired effect, sometimes in an organ other than the target organ.        
    Therapeutic Index A quantitative measurement of the relative safety of a drug that compares the amount of drug that produces a therapeutic effect versus the amount of drug that produces a toxic effect. Medication with a large therapeutic index is safer than a medication with a small therapeutic index.        
    Therapeutic Window The dosing window in which the safest and most effective treatment will occur.        
    American Nurses Association (ANA) The professional organization that represents the interests of the nation’s 4 million registered nurses.        
    Beneficence To “do good.”        
    Black Box Warnings The strongest warnings issued by the Federal Drug Association (FDA) that signify a drug carries a significant risk of serious or life-threatening adverse effects.        
    Code of Ethics for Nurses Developed by the American Nurses Association as a guide for carrying out nursing responsibilities in a manner consistent with quality in nursing care and the ethical obligations of the profession.        
    Cultural Competence: The process by which nurses demonstrate culturally congruent practice.        
    Culturally Congruent Practice The application of evidence-based nursing that is in agreement with the preferred cultural values, beliefs, worldview, and practices of the healthcare consumer and other stakeholders.        
    Do Not Crush List A list of medications that should not be crushed, often due to a sustained-release formulation.        
    Drug Diversion The transfer of any legally prescribed controlled substance from the individual for whom it was prescribed to another person for any illicit use.        
    Error-Prone Abbreviations Abbreviations, symbols, and dose designations that are frequently misinterpreted and involved in harmful medication errors.        
    Five Rights of Medication Administration Standards of practice that require the following information is confirmed prior to each administration of medication: right patient, right drug, right dose, right time, and right route.        
    Health Literacy The degree to which individuals have the capacity to obtain, process, and understand basic health information needed to make appropriate health decisions.        
    High-Risk Medications Drugs that bear a heightened risk of causing significant patient harm when they are used in error.        
    Inappropriate Polypharmacy Present when one or more medicines are prescribed that are not or no longer needed.        
    Joint Commission A national organization that accredits and certifies health care organizations in the United States.        
    Look-Alike and Sound-Alike (LASA) Drugs Medications that require special safeguards to reduce the risk of errors and minimize harm.        
    Maleficence Causing harm to patients.        
    National Patient Safety Goals (NPSGs) Goals established by the Joint Commission to help accredited organizations address specific areas of concern related to patient safety.        
    Nursing The protection, promotion, and optimization of health and abilities, prevention of illness and injury, facilitation of healing, alleviation of suffering through the diagnosis and treatment of human response, and advocacy in the care of individuals, families, groups, communities, and populations, as defined by the American Nurses Association.        
    Nursing Process Standards of Practice that include Assessment; Diagnosis; Outcome Identification; Planning; Implementation; and Evaluation components of providing patient care.        
    Nursing Scope and Standards of Practice A document created by the American Nurses Association that outlines professional nursing performance according to national standards.        
    Polypharmacy The concurrent use of multiple medications.        
    Prescription Drug Monitoring Programs (PDMP) A statewide electronic database that collects designated data on substances dispensed in a state to address prescription drug abuse, addiction, and diversion.        
    Professional Assistance Procedure A voluntary non-disciplinary program to provide support for credentialed professionals in Wisconsin with substance abuse disorder who are committed to their own recovery.        
    Registered Nurse (RN) An individual who is educationally prepared and licensed by a state to practice as a registered nurse.        
    Root Cause Analysis An analysis after an error occurs to help identify not only what and how an event occurred, but also why it happened. When investigators are able to determine why an event or failure occurred, they can create workable corrective measures that prevent future errors from occurring.        
    Safety Culture The culture of a health care agency that empowers staff to speak up about risks to patients and to report errors and near misses, all of which drive improvement in patient care and reduce the incident of patient harm.        
    Scheduled Medications The Controlled Substances Act (CSA) places all substances that are regulated under existing federal law into one of five schedules, ranging from Schedule I drugs with a high potential for abuse and the potential to create severe psychological and/or physical dependence, to Schedule V drugs with the least potential for abuse.        
    Social Determinants of Health Poverty, education, safe medication, and other healthcare disparities that affect a patient’s health.        
    Standards of Practice Authoritative statements of duties by the American Nursing Association that all registered nurses, regardless of role, population, or specialty, are expected to perform competently. Standards of Practice include Assessment, Diagnosis, Outcome Identification, Planning, Implementation, and Evaluation components of providing patient care.        
    Standards of Professional Performance Describe a competent level of behavior in the professional role, including activities related to ethics, culturally congruent practice, communication, collaboration, leadership, education, evidence-based practice, and quality of practice as defined by the American Nursing Association.        
    State Nurse Practice Act Laws enacted by state legislatures setting professional standards of nursing care to which nurses are held accountable by the State Board of Nursing.        
    State Board of Nursing A group of officials who enforce the State Nurse Practice Act.        
    Substance Use Disorder A pattern of behaviors that ranges from misuse to dependency or addiction, whether it is alcohol, legal drugs, or illegal drugs. Addiction is a complex disease with serious physical, emotional, financial, and legal consequences.        
    Antagonistic Interactions Concurrent administration of two drugs causes harmful effects such as a decrease of drug activity, decreased therapeutic levels due to increased metabolism and elimination, or increased potential for toxicity due to decreased metabolism and elimination. An example of an antagonistic interaction is taking antacids with antibiotics, causing decreased absorption of the antibiotic.        
    Antifungal Medications that are used to treat fungal infections. For example, nystatin is used to treat Candida Albicans, a fungal infection.        
    Antiviral Medications used to treat viral infections. For example, Tamiflu is used to treat influenza.        
    Bactericidal Antimicrobial drugs that kill their target bacteria.        
    Bacteriostatic Antimicrobial drugs that cause bacteria to stop reproducing but may not ultimately kill the bacteria.        
    Black Box Warnings The strongest warnings issued by the Federal Drug Administration (FDA) that signify the drug carries a significant risk of serious or life-threatening adverse effects.        
    Broad-Spectrum Antimicrobial An antibiotic that targets a wide variety of bacterial pathogens, including both gram-positive and gram-negative species.        
    Clostridium Difficile (C-diff) Clostridium difficile causes pseudomembranous colitis, a superinfection that can be caused by broad spectrum antibiotic therapy.        
    Culture A test performed on various body substances for the presence of bacteria or fungus.        
    Dose Dependent A more significant response occurs in the body when the medication is administered in large doses to provide a large amount of medication to the site of infection for a short period of time.        
    Gram-Positive: Gram-positive bacteria are classified by the color they turn after a chemical called Gram stain is applied to them. Infections caused by Streptococcus and Staphylococcus bacteria are examples of gram-positive infections.        
    Gram-Negative Gram-negative bacteria are classified by the color they turn after a chemical called Gram stain is applied to them. Escherichia Coli (also known as E. Coli) is an example of a gram-negative infection.        
    Gram Stain A test used to quickly diagnose types of bacterial infection. Gram-positive and gram-negative bacteria stain differently because their cell walls are different. Identification of bacteria as gram positive or gram negative assists the healthcare provider in selecting an appropriate antibiotic to treat the infection.        
    Half-Life The rate at which 50% of a drug is eliminated from the bloodstream.        
    Indications The use of a drug for treating a particular condition or disease. The FDA determines if there is enough evidence for a labeled indication of a drug. Providers may also prescribe medications for off-label indications if there is reasonable scientific evidence that the drug is effective, but these uses have not been approved by the FDA.        
    Mechanism of Action The way in which a drug affects microbes at the cellular level.        
    Methicillin-Resistant S. Aureus (MRSA) An infection caused by Methicillin-resistant Staphylococcus aureus that is difficult to treat because it exhibits resistance to nearly all available antibiotics.        
    Narrow-Spectrum Antimicrobial An antibiotic that targets only specific subsets of bacterial pathogens.        
    Pathogen An organism causing disease to its host.        
    Prototype A common individual drug that represents a drug class or group of medications having similar chemical structures, mechanism of actions, and modes of action.        
    Resistance A characteristic of bacteria when sensitivity analysis is performed demonstrating lack of effective treatment by a particular antibiotic.        
    Sensitivity Analysis A test performed in addition to a culture to select an effective antibiotic to treat a microorganism.        
    Superinfection A secondary infection in a patient having a preexisting infection. C-diff and yeast infections as a result of antibiotic therapy are examples of superinfections.        
    Synergistic Interaction Concurrent drug administration producing a synergistic interaction that is better than the efficacy of either drug alone. An example of synergistic drug combinations is trimethoprim and sulfamethoxazole (Bactrim).        
    Time Dependent Time dependency occurs when greater therapeutic effects are seen with lower blood levels over a longer period of time.        
    Vancomycin-Resistant S. Aureus (VRSA) An infection caused by Vancomycin-resistant Staphylococcus aureus that is difficult to treat because it exhibits resistance to nearly all available antibiotics.        
    Acetylcholine (ACh) Binds to both nicotinic receptors and muscarinic receptors in the PNS.        
    Adrenergic Postganglionic neuron where neurotransmitters norepinephrine and epinephrine are released. Includes alpha (α) receptors and beta (β) receptors.        
    Adrenergic Agonist Mimics the effects of the body’s natural SNS stimulation on alpha (α) and beta (β) receptors. Also called sympathomimetics.        
    Adrenergic Antagonist Blocks the effects of the SNS receptors.        
    Anticholinergics Inhibit acetylcholine (ACh), which allows the SNS to dominate. Also called parasympatholytics or muscarinic antagonists. Overall use is to relax smooth muscle.        
    Autonomic Nervous System Controls cardiac and smooth muscle, as well as glandular tissue; associated with involuntary responses.        
    Catecholamines Include norepinephrine, epinephrine, and dopamine. Stimulate the adrenergic receptors.        
    Central Nervous System (CNS) Anatomical division of the nervous system located within the cranial and vertebral cavities, namely the brain and spinal cord.        
    Cholinergic Postganglionic neuron where acetylcholine (ACh) is released that stimulates nicotinic receptors and muscarinic receptors. Also relating to drugs that inhibit, enhance, or mimic the action of ACh.        
    Chronotropic Drugs may change the heart rate and rhythm by affecting the electrical conduction system of the heart and the nerves that influence it, such as by changing the rhythm (increasing) produced by the sinoatrial node. Positive chronotropes increase heart rate; negative chronotropes decrease heart rate.        
    Dromotropic Stimulation causes increases speed of conduction between SA and AV node.        
    Fight-or-Flight Response The response when the SNS is stimulated, causing the main effects of increased heart rate, increased blood pressure, and bronchodilation.        
    Glyconeogenesis The breakdown of glycogen into glucose, causing elevated blood glucose.        
    Homeostasis (in ANS) Balance between the SNS and PNS. At each target organ, dual innervation determines activity. For example, SNS stimulation causes the heart rate to increase, whereas PNS stimulation causes the heart rate to decrease.        
    Hyperglycemia Elevated blood glucose.        
    Inotropic Stimulation causes increased force of contraction.        
    Involuntary Responses Responses that the brain controls without the need for conscious thought.        
    Motor Neurons Consist of the somatic nervous system that stimulates voluntary movement of muscles and the autonomic nervous system that controls involuntary responses.        
    Muscarinic Agonists Also called parasympathomimetics. Primarily cause smooth muscle contraction, resulting in decreased HR, bronchoconstriction, increased gastrointestinal/genitourinary tone, and pupil constriction.        
    Neurons Cells that carry electrical impulses to the synapse of a target organ.        
    Nonselective Beta Blockers Medications that block both Beta-1 and Beta-2 receptors, thus affecting both the heart and lungs.        
    Parasympathetic Division (PNS) Includes nerves outside the brain and spinal cord. Associated with the “rest and digest” response. Stimulation of PNS causes decreased heart rate, decreased blood pressure via vasodilation, bronchial constriction, and stimulates intestinal motility, salivation, and relaxation of the bladder.        
    Parasympatholytics: Inhibit acetylcholine (ACh), which allows the SNS to dominate. Also called anticholinergics or muscarinic antagonists.        
    Parasympathomimetics Also called muscarinic agonists. Primarily cause smooth muscle contraction, resulting in decreased HR, bronchoconstriction, increased GI/GU tone, and pupil constriction.        
    Peripheral Nervous System (PNS) An anatomical division of the nervous system that is largely outside the cranial and vertebral cavities, namely all parts except the brain and spinal cord.        
    Postganglionic Neurons: Differ for the SNS and PNS branches. Postganglionic neurons of the autonomic system are classified as either cholinergic, meaning that acetylcholine (ACh) is released, or adrenergic, meaning that norepinephrine is released.        
    Preganglionic Neurons All preganglionic neurons (in the SNS and PNS) release acetylcholine (ACh).        
    Selective Beta Blocker Medications that mostly inhibit B1 receptors.        
    Sensory Neurons Sense the environment and conduct signals to the brain that become a conscious perception of that stimulus.        
    “SLUDGE” Mnemonic for the effects of anticholinergics: Salivation decreased, Lacrimation decreased, Urinary retention, Drowsiness/dizziness, GI upset, Eyes (blurred vision/dry eyes).        
    Somatic Nervous System Causes contraction of skeletal muscles; associated with voluntary responses.        
    Sympathetic Division (SNS) Associated with the “fight-or-flight response.” Stimulation causes the main effects of increased heart rate, increased blood pressure via the constriction of blood vessels, and bronchodilation.        
    Sympathomimetics Mimic the effects of the body’s natural SNS stimulation of adrenergic receptors. Also called adrenergic agonists.        
    Synapse The connection between the neuron and its target cell.        
    Allergies Allergies occur when the immune system reacts to a foreign substance and makes antibodies that identify a particular allergen as harmful, even though it isn’t.        
    Anaphylaxis A severe, potentially life-threatening allergic reaction. It can occur within seconds or minutes of exposure to something you’re allergic to, such as peanuts or bee stings.        
    Cyanotic A bluish or purplish discoloration (as of skin) due to deficient oxygenation of the blood.        
    Gas Exchange The process at the alveoli level where blood is oxygenated and carbon dioxide, the waste product of cellular respiration, is removed from the body.        
    Pallor A deficiency of color especially of the face; paleness.        
    Paradoxical Effect An effect that is opposite to what is expected.        
    Respiratory Rate The total number of breaths, or respiratory cycles, that occur each minute. A child under 1 year of age has a normal respiratory rate between 30 and 60 breaths per minute, but by the time a child is about 10 years old, the normal rate is closer to 18 to 30. By adolescence, the normal respiratory rate is similar to that of adults, 12 to 18 breaths per minute.        
    Sputum Matter expectorated from the respiratory system and especially the lungs that is composed of mucus but may contain pus, blood, fibrin, or microorganisms (such as bacteria) in diseased states.        
    Afterload: The tension that the ventricles must develop to pump blood effectively against the resistance in the vascular system.        
    Anticoagulant Any substance that opposes coagulation.        
    Arrhythmia: A deviation from the normal pattern of impulse conduction and contraction of the heart, which if serious and untreated, can lead to decreased cardiac output and death.        
    Arteriosclerosis: A condition when compliance in an artery is reduced and pressure and resistance within the vessel increase. This is a leading cause of hypertension and coronary heart disease, as it causes the heart to work harder to generate a pressure great enough to overcome the resistance.        
    Artery A blood vessel that carries blood away from the heart (except for pulmonary arteries that carry oxygenated blood from the lungs back to the heart).        
    Atherosclerosis A buildup, called plaque, that can narrow arteries enough to impair blood flow.        
    Blood pressure A type of hydrostatic pressure, or the force exerted by blood on the walls of the blood vessels or the chambers of the heart.        
    Capillaries Smallest arteries where nutrients and wastes are exchanged at the cellular level.        
    Cardiac Output (CO) To calculate this value, multiply stroke volume (SV), the amount of blood pumped by each ventricle, by heart rate (HR), in contractions per minute (or beats per minute, bpm). It can be represented mathematically by the following equation: CO = HR × SV.        
    Cerebrovascular Accident (CVA) Lack of blood flow to the brain that can cause irreversible brain damage, often referred to as a “stroke.”        
    Coagulation The formation of a blood clot.        
    Compliance The ability of any compartment to expand to accommodate increased content. The greater the compliance of an artery, the more effectively it is able to expand to accommodate surges in blood flow without increased resistance or blood pressure. Veins are more compliant than arteries and can expand to hold more blood. When vascular disease causes stiffening of arteries, compliance is reduced and resistance to blood flow is increased.        
    Contractility The force of contraction of the heart.        
    Diastole The period of relaxation that occurs as the chambers fill with blood.        
    Edema The presence of excess tissue fluid around the cells.        
    Embolus When a portion of a thrombus breaks free from the vessel wall and enters the circulation. An embolus that is carried through the bloodstream can be large enough to block a vessel critical to a major organ. When it becomes trapped, an embolus is called an embolism. In the heart, brain, or lungs, an embolism may accordingly cause a heart attack, a stroke, or a pulmonary embolism.        
    Fibrillation: An uncoordinated beating of the heart, which if serious and untreated, can lead to decreased cardiac output and death.        
    Fibrinolysis The gradual degradation of a clot.        
    Hemostasis The process by which the body temporarily seals a ruptured blood vessel and prevents further loss of blood.        
    Hyperlipidemia Elevated cholesterol levels in the blood that increase a patient’s risk for heart attack and stroke.        
    Hypertension Chronically elevated blood pressure.        
    Hypervolemia: Excessive fluid volume caused by retention of water and sodium, as seen in patients with heart failure, liver cirrhosis, and some forms of kidney disease.        
    Hypovolemia: Decreased blood volume that may be caused by bleeding, dehydration, vomiting, severe burns, or by diuretics used to treat hypertension. Treatment typically includes intravenous fluid replacement.        
    International Normalized Ratio (INR) A blood test used to monitor the effects of warfarin and to achieve therapeutic range, generally between 2.0 and 3.5 based on the indication.        
    Ischemia Reduced blood flow to the tissue region “downstream” of the narrowed vessel.        
    Loop of Henle A component of the nephron where loop diuretics act to eliminate sodium and water.        
    Myocardial Infarction (MI) Commonly referred to as a heart attack, resulting from a lack of blood flow (ischemia) and oxygen to a region of the heart, resulting in death of the cardiac muscle cells.        
    Negative Inotropic factors: Factors that decrease contractility.        
    Partial Thromboplastin Time (PTT) A blood test used to monitor how long it takes for a patient’s blood to clot. PTT is used for patients receiving IV heparin therapy to achieve therapeutic range. Dosage is considered adequate when the activated partial thromboplastin time (APTT) is 1.5 to 2 times the normal or when the whole blood clotting time is elevated approximately 2.5 to 3 times the control value.        
    Positive inotropic factors Factors that increase contractility.        
    Preload The amount of blood in the atria just prior to atrial contraction.        
    Prothrombin Time (PT) A blood test that measures how long it takes for a patient’s blood to clot. PT is used to monitor the effects of warfarin in preventing clot formation.        
    Renin-Angiotensin-Aldosterone System (RAAS) Renin converts the plasma protein angiotensinogen into its active form—Angiotensin I. Angiotensin I circulates in the blood and is then converted into angiotensin II in the lungs. This reaction is catalyzed by the angiotensin-converting enzyme (ACE). Angiotensin II is a powerful vasoconstrictor, greatly increasing blood pressure. It also stimulates the release of ADH and aldosterone, a hormone produced by the adrenal cortex. Aldosterone increases the reabsorption of sodium into the blood by the kidneys, causing reabsorption of water and increasing blood volume and raising blood pressure.        
    Sinoatrial (SA) node Normal cardiac rhythm is established by the sinoatrial (SA) node. The SA node has the highest inherent rate of depolarization and is known as the pacemaker of the heart.        
    Sinus rhythm Normal electrical pattern followed by contraction of the heart.        
    Stroke Volume (SV) The amount of blood that both ventricles pump during each contraction, normally in the range of 70–80 mL.        
    Systole The period of contraction that the heart undergoes while it pumps blood into circulation.        
    Thrombus An aggregation of platelets, erythrocytes, and WBCs trapped within a mass of fibrin strands that adhere to the vessel wall and decrease the flow of blood or totally block the flow of blood.        
    Transient Ischemic Attack (TIA): Occurs when blood flow is interrupted to the brain, even for just a few seconds, resulting in loss of consciousness or temporary loss of neurological function.        
    Veins Blood vessels that conduct blood toward the heart (except for pulmonary veins that carry deoxygenated blood from the heart to the lungs).        
    Venous reserve Volume of blood located in venous networks within the liver, bone marrow, and integument.        
    Adsorption The adhesion of molecules to a surface. For example, bismuth salicylate coats the walls of the GI tract and binds the causative bacteria or toxin for elimination from the GI tract through the stool.        
    Antacids Used to neutralize stomach acid and reduce the symptoms of heartburn.        
    Antidiarrheals Relieve the symptoms of diarrhea, such as an increased frequency and urgency when passing stools, but do not eliminate the cause of it.        
    Antimotility medications Medications that help to treat diarrhea by slowing peristalsis.        
    Area Postrema A structure in the medulla oblongata in the brainstem that controls vomiting. Its location in the brain also allows it to play a vital role in the control of autonomic functions by the central nervous system.        
    Chemoreceptor Trigger Zone (CTZ) Area in the brain that responds directly to toxins in the bloodstream and also receives stimuli from several other locations in the body that stimulate the vomiting center.        
    Cytochrome P-450 enzymes Enzymes produced from the cytochrome P450 genes involved in the formation (synthesis) and breakdown (metabolism) of various molecules, chemicals, and medications within cells.        
    Defecation The digestive process where undigested materials are removed from the body as feces.        
    Diarrhea The passage of three or more loose or liquid stools per day (or more frequent passage than is normal for the individual).        
    Gastroenteritis Infection of the intestines.        
    Gastroesophageal reflux disease (GERD) Caused by excessive hydrochloric acid that tends to back up, or reflux, into the lower esophagus.        
    Hematemesis Blood in the vomit.        
    Hypercalcemia: Elevated levels of calcium in the bloodstream.        
    Intrinsic factor Necessary for the absorption of vitamin B12 in the small intestine.        
    Osmotic agents Cause water to be retained with the stool, increasing the number of bowel movements and softening the stool so it is easier to pass.        
    Parietal cells Cells in the gastric glands that produce and secrete hydrochloric acid (HCl) and intrinsic factor.        
    Pepsin A digestive enzyme.        
    Peptic ulcer disease (PUD) Occurs when gastric or duodenal ulcers are caused by the breakdown of GI mucosa by pepsin in combination with the caustic effects of hydrochloric acid.        
    Probiotics Used for the prevention and treatment of diarrhea by restoring normal bacteria flora in the gastrointestinal tract.        
    Prokinetic Medications used to promote peristalsis to empty the gastrointestinal tract and reduce nausea.        
    Proton pump inhibitors (PPIs) Bind to the hydrogen-potassium ATPase enzyme system of the parietal cell and inhibit the release of hydrogen ions into the stomach.        
    Rebound hyperacidity A side effect of medication causing elevated levels of hydrochloric acid in the stomach after the medication is discontinued.        
    Serotonin Syndrome Symptoms associated with serotonin syndrome may include the following: mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, with or without gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea).        
    Stimulants Laxatives that cause the intestines to contract, inducing stool to move through the colon.        
    Stool softeners Laxatives that facilitate movement of water and fats into stool to make it soft and improve regularity of bowel movements.        
    Stress-related mucosal damage A common condition in hospitalized patients that can lead to PUD.        
    Stress Ulcer Prophylaxis Medication to prevent the formation of stress ulcers.        
    Surface epithelium cells Cells found within the lining of the stomach that secrete mucus as a protective coating.        
    THC Tetrahydrocannabinoids found in marijuana.        
    Vestibular system An area located within the inner ear that gives a sense of balance and spatial orientation for the purpose of coordinating movement with balance.        
    Vomiting Center (VC) An area in the brain that initiates vomiting by inhibiting peristalsis and producing retro-peristaltic contractions beginning in the small bowel and ascending into the stomach. It also produces simultaneous contractions in the abdominal muscles and diaphragm that generate high pressures to propel the stomach contents upwards.        
    Action potential A change in voltage of a cell membrane in response to a stimulus that results in transmission of an electrical signal; unique to neurons and muscle fibers.        
    Acute dystonia Painful muscle spasms.        
    Affective mood disorders Mental illness such such as major depression.        
    Akathisia Distressing motor restlessness.        
    Blood-brain barrier (BBB) A physiological barrier between the circulatory system and the central nervous system that establishes a privileged blood supply, restricting the flow of substances into the CNS.        
    Bradykinesia Slowness in initiation and execution of voluntary movements.        
    Central nervous system (CNS) Anatomical division of the nervous system located within the cranial and vertebral cavities, namely the brain and spinal cord.        
    Chemical synapse Connection between two neurons, or between a neuron and its target, where a neurotransmitter diffuses across a very short distance.        
    Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) A condition reported in patients taking antiepileptic drugs. Some of these events have been fatal or life threatening. DRESS typically presents with fever, rash, lymphadenopathy, and/or facial swelling.        
    Dystonia Inappropriate and continuous muscle contraction.        
    Electrical synapse Connection between two neurons, or any two electrically active cells, where ions flow directly through channels spanning their adjacent cell membranes.        
    Extrapyramidal symptoms Involuntary motor symptoms similar to those associated with Parkinson’s disease. Includes symptoms such as akathisia (distressing motor restlessness) and acute dystonia (painful muscle spasms). Often treated with anticholinergic medications such as benztropine and trihexyphenidyl.        
    Gait disturbance An abnormal way of walking, such as shuffling feet.        
    Hypertensive crisis Severe hypertension (blood pressure greater than 180/120 mm Hg) with evidence of organ dysfunction. Symptoms may include occipital headache (which may radiate frontally), palpitations, neck stiffness or soreness, nausea or vomiting, sweating, dilated pupils, photophobia, shortness of breath, or confusion. Either tachycardia or bradycardia may be present and may be associated with constricting chest pain. Seizures may also occur. Intracranial bleeding, sometimes fatal, has been reported in association with the increase in blood pressure.        
    Mania Periods of extreme highs in bipolar disorder. Manic episodes may include these symptoms: rapid speech, hyperactivity, reduced need for sleep, flight of ideas, grandiosity, poor judgement, aggression/hostility, risky sexual behavior, neglected basic self-care, or decreased impulse control.        
    Nerve Cord-like bundle of axons located in the peripheral nervous system that transmits sensory input and response output to and from the central nervous system.        
    Neuroleptic malignant syndrome (NMS) Potentially life-threatening adverse effect that includes high fever, unstable blood pressure, and myoglobinemia.        
    Neuron(s) Neural tissue cell that is primarily responsible for generating and propagating electrical signals into, within, and out of the nervous system.        
    Neurotransmitter Chemical signal that is released from the synaptic end bulb of a neuron to cause a change in the target cell.        
    Ophthalmoplegia Weakness in eye muscles.        
    Orthostatic hypotension A significant change in blood pressure from lying to sitting to standing.        
    Peripheral nervous system (PNS) An anatomical division of the nervous system that is largely outside the cranial and vertebral cavities, namely all parts except the brain and spinal cord.        
    Postural instability Abnormal fixation of posture (stoop when standing), problems with equilibrium, and righting reflex.        
    Rigidity Increased muscle tone and increase resistance to movement. As severity increases, there may be cogwheel rigidity.        
    Serotonin syndrome May occur when taking serotonin medications. Includes mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination) and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Serotonin syndrome, in its most severe form, can resemble neuroleptic malignant syndrome, which includes hyperthermia, muscle rigidity, autonomic instability with possible rapid fluctuation of vital signs, and mental status changes.        
    Status epilepticus A state of repeated or continuous seizures.        
    Tardive dyskinesia Involuntary contraction of the oral and facial muscles (such as tongue thrusting) and wavelike movements of the extremities.        
    Thalamus The region of the central nervous system that acts as a relay for sensory pathways.        
    Threshold The membrane voltage at which an action potential is initiated.        
    Tremor Usually tremor at rest; when person sits, the arms shake, but tremor stops when person attempts to grab something.        
    A1C A lab test used to assess long-term blood glucose levels over 3 months. The general A1C target level is less than 7%.        
    Adrenal cortex A component of the hypothalamic-pituitary-adrenal (HPA) axis that produces the steroid hormones important for the regulation of the stress response, blood pressure and blood volume, nutrient uptake and storage, fluid and electrolyte balance, and inflammation.        
    Adrenal medulla Neuroendocrine tissue composed of postganglionic sympathetic nervous system (SNS) neurons that are stimulated by the autonomic nervous system to secrete hormones epinephrine and norepinephrine.        
    Aldosterone A mineralocorticoid released by the adrenal cortex that controls fluid and electrolyte balance through the regulation of sodium and potassium.        
    Antidiuretic hormone (ADH) ADH is released by the posterior pituitary in response to stimuli from osmoreceptors indicating high blood osmolarity. Its effect is to cause increased water reabsorption by the kidneys. As more water is reabsorbed by the kidneys, the greater the amount of water that is returned to the blood, thus causing a decrease in blood osmolarity. ADH is also known as vasopressin because, in very high concentrations, it causes constriction of blood vessels, which increases blood pressure by increasing peripheral resistance.        
    Basal insulin Long-acting (insulin glargine or insulin detemir) or intermediate-acting (NPH) insulin.        
    Basal Metabolic Rate The amount of energy used by the body at rest.        
    Blood osmolarity The concentration of solutes (such as sodium and glucose) in the blood.        
    Diabetes insipidus (DI) A disease characterized by underproduction of ADH that causes chronic dehydration.        
    Endocrine gland Gland that secretes hormones that target other organs.        
    Exocrine gland Gland that secretes digestive enzymes.        
    General adaptation syndrome (GAS) The pattern in which the body responds in different ways to stress: the alarm reaction (otherwise known as the fight-or-flight response,) the stage of resistance, and the stage of exhaustion.        
    Glycolysis Stimulated by insulin, the metabolism of glucose for generation of ATP.        
    Goiter A visible enlargement of the thyroid gland when there is hyperstimulation of TSH due to deficient levels of T3 and T4 hormones in the bloodstream or an autoimmune reaction in which antibodies overstimulate the follicle cells of the thyroid gland, causing hyperthyroidism.        
    Hormones Chemical signals sent by the endocrine organs and transported via the bloodstream throughout the body where they bind to receptors on target cells and induce a characteristic response.        
    Humoral stimuli Changes in blood levels of non-hormone chemicals that cause an endocrine gland to release or inhibit a hormone to maintain homeostasis. For example, high blood sugar causes the pancreas to release insulin.        
    Hyperglycemia: Elevated blood glucose levels.        
    Hyperparathyroidism A disorder caused by an overproduction of PTH that results in excessive calcium resorption from bone, causing significantly decreased bone density and spontaneous fractures, decreased responsiveness of the nervous system, and calcium deposits in the body’s tissues and organs, impairing their functioning.        
    Hyperthyroidism Abnormally elevated blood level of thyroid hormones T3 and T4, often caused by a pituitary tumor, thyroid tumor, or autoimmune reaction in which antibodies overstimulate the follicle cells of the thyroid gland.        
    Hypoglycemia A blood glucose level below 70 mg/dL; severe hypoglycemia refers to a blood glucose level below 40.        
    Hypoparathyroidism Abnormally low blood calcium levels caused by parathyroid hormone deficiency, which may develop following thyroid surgery. Low blood calcium can cause muscle twitching, cramping, spasms, or convulsions; severe deficits can paralyze muscles, including those involved in breathing, and can be fatal.        
    Hypothalamic-pituitary-adrenal (HPA) axis The hypothalamus stimulates the release of ACTH from the pituitary, which then stimulates the adrenal cortex to produce the hormone cortisol and steroid hormones important for the regulation of the stress response, blood pressure and blood volume, nutrient uptake and storage, fluid and electrolyte balance, and inflammation.        
    Hypothalamus–pituitary complex The “command center” of the endocrine system that secretes several hormones that directly produce responses in target tissues, as well as hormones that regulate the synthesis and secretion of hormones of other glands. In addition, the hypothalamus–pituitary complex coordinates the messages of the endocrine and nervous systems.        
    Hypothyroidism Abnormally low blood levels of thyroid hormones T3 and T4 in the bloodstream.        
    Insulin A hormone that facilitates the uptake of glucose into skeletal and adipose body cells.        
    Mineralocorticoids Hormones released by the adrenal cortex that regulate body minerals, especially sodium and potassium, that are essential for fluid and electrolyte balance. Aldosterone is the major mineralocorticoid.        
    Negative feedback loop Characterized by the inhibition of further secretion of a hormone in response to adequate levels of that hormone.        
    Neural stimuli Released in response to stimuli from the nervous system. For example, the activation of the release of epinephrine and norepinephrine in the fight-or-flight response is stimulated by the sympathetic nervous system.        
    Osmoreceptors Specialized cells within the hypothalamus that are sensitive to the concentration of sodium ions and other solutes in the bloodstream.        
    Parathyroid hormone (PTH) The hormone released by parathyroid glands and is involved in the regulation of blood calcium levels.        
    Prandial insulins During or relating to the eating of food.        
    Tropic hormones Hormones that turn on or off the function of other endocrine glands, including ACTH, FSH, LH, and TSH.        
    Type 1 diabetes An autoimmune disease that affects the beta cells of the pancreas so they do not produce insulin; thus, synthetic insulin must be administered by injection or infusion.        
    Type 2 diabetes A condition where the body’s cells become resistant to the effects of insulin. Over time, the beta cells become exhausted and if blood glucose levels cannot be controlled through a healthy diet and exercise, then oral diabetic medication must be implemented and eventually insulin administration may be required.        
    Acute Pain Pain that usually starts suddenly and has a known cause, like an injury or surgery. It normally gets better as your body heals and lasts less than three months.        
    Adjuvant analgesics Drugs with a primary indication other than pain that have analgesic properties in some painful conditions. The group includes numerous drugs in diverse classes such as gabapentin (an anticonvulsant) or amitriptyline (a tricyclic antidepressant).        
    Chronic pain Pain that lasts six months or more and can be caused by a disease or condition, injury, medical treatment, inflammation, or an unknown reason.        
    Immune-mediated disease process Occurs when the body’s immune system attacks the central nervous system.        
    Misuse: The use of illegal drugs and/or the use of prescription drugs in a manner other than as directed by a doctor, such as using in greater amounts, more often, or longer than told to take a drug or using someone else’s prescription.        
    Muscle Spasticity Condition in which certain muscles are continuously contracted. This contraction causes stiffness or tightness of the muscles and can interfere with normal movement, speech, and gait. Spasticity is usually caused by damage to the portion of the brain or spinal cord that controls voluntary movement.        
    Nociceptors: Nerve endings that selectively respond to painful stimuli and send pain signals to the brain and spinal cord.        
    Non-pharmacologic therapy: Treatments that do not involve medications, including physical treatments (e.g., heat or cold therapy, exercise therapy, weight loss) and cognitive-behavioral treatments (e.g., distractions/diversions and cognitive behavioral therapy).        
    Patient controlled analgesia (PCA) To receive the opioid, the patient pushes a button on the PCA device, which releases a specific dose but also has a lockout mechanism to prevent an overdose. Included with hydromorphone or fentanyl.        
    Prostaglandins Produced in nearly all cells and are part of the body’s way of dealing with injury and illness. Prostaglandins act as signals to control several different processes depending on the part of the body in which they are made. Prostaglandins are made at the sites of tissue damage or infection, where they cause inflammation, pain, and fever as part of the healing process.        
    Vertigo A sense of spinning dizziness. It is a symptom of a range of conditions. It can happen when there is a problem with the inner ear, brain, or sensory nerve pathway.        
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