Pharmacology Week 1

three domains of learning

cognitive, affective, psychomotor

standing order

given for specific number of doses

Additive effect (Table 2-1)

2 drugs w similar actions are taken for increased affect (i.e hydrocodone + aceminophen = added analgesic effect)

Antagonistic effect (table 2-1)

- one drug interferes with the action of another (i.e. tetracycline + antacid = decreased absorption of the tetracycline).

Secondary sources include (for assessment):

- relatives and significant others - medical records - lab reports

Nocebo effect

A patient's negative expectations can result in a less-than-optimal outcome

Placebo effect

A patient's positive expectation can positively affect the outcome

Factors Affecting ABSORBTION in GERIATRIC PTS

- IM absorption erratic - Reduced salivary flow makes swallowing difficult - Transdermal absorption hard to predict - Timed-release/enteric-coated tablets cannot be crushed - Reduced GI acidity affects absorption - Slower gastric emptying time - Decreased GI motility and blood flow

Factors Affecting Drug Action in NEONATES

- IM absorption erratic - reduced gastric acidity

What is the MedWatch form used for?

- Identifying adverse effects of a drug in the general population - Healthcare practitioners make a significant contribution to the knowledge of drug safety by reporting adverse effects to the FDA using the MedWatch program for the voluntary reporting of adverse events and product problems. This method of identifying adverse effects of a drug in the general population is part of the postmarketing surveillance phase of drug development. More than 200,000 MedWatch forms are filed with the FDA annually. MedWatch is not designed to track the numbers of prescriptions written for a specific drug; is not a program involved in determining the therapeutic effectiveness of a drug; and is not involved in assessing the acceptability of a drug to individual patients.

STAT order

single order carried out immediately

Affective Domain

Involves feelings, needs, values, and opinion

Cognitive Domain

Involves learning and storing knowledge

psychomotor domain

(pt demonstartes a learned skill or procedure) The domain involved in the learning of a new procedure or skill; often called the doing domain.

Drug classifications Known to be Teratogenic

- Androgenic and estrogenic hormones - ACE inhibitors - ethanol -tetracycline - Thalidomide - vitamin A - warfarin - Angiotensin II receptor antagonists - Anticonvulsants - antimanic agents - antithyroid - Chemotherapy - statins -cocaine

Use of Monitoring Parameters: Pregnant Women

- Avoid drugs if at all possible - When taking woman's history, be alert to possibility of pregnancy - Instruct patient to avoid drugs, alcohol, and tobacco - Try nonpharmacologic treatments before using medicines - Avoid herbal medicines

Unbound Drugs

- Drugs are bound to proteins in the blood during transportation - The more a drug is "bound" to a protein, the less available it is to the circulation - Some medications can cause binding or unbinding of another medication, increasing or decreasing its effect

Single order

Medication that is to be given only once, and at a specific time, such as a preoperative order.

Factors Affecting Drug Action in INFANTS

- Topical absorption increased

PRN order

administer as needed

Patient responses and compliance (for teaching) depend on numerous variables

- Beliefs and perceptions - Effects on lifestyle - Acceptance/denial of illness - Stress

Before administering medication, the nurse must have:

- Current license to practice - Clear policy statement authorizing the act - Signed medication order - Understanding of rationale for drug use - Understanding of: drug action, dosing, dilution, route and rate of administration, common and serious adverse effects, and contraindications

Absorption

- Drug is transferred from entry site into the body's circulating fluids - Absorption rate depends on route, blood flow, and solubility of the drug - Subcutaneous and intramuscular injection absorption is affected by circulation - Intravenous medications are absorbed fastest - Topical medications applied to the skin can be influenced by skin thickness and hydration

A patient with diabetes has elevated blood glucose levels and exhausted their insulin (Humulin R) medication supply. The patient cannot delay taking insulin until the primary healthcare provider is consulted. What is the correct action by the licensed practical nurse in this situation according to the Canadian Food and Drugs Act and Regulations?

(ONLY IN CANADA) - Collaborating with the pharmacist to issue insulin to the patient immediately - According to the Food and Drugs Act and Regulations, Schedule II drugs such as insulin can be obtained directly from a pharmacist. Therefore, the licensed practical nurse should collaborate with the pharmacist to issue insulin immediately to ensure the patient's safety. Herbal products do not ensure the patient's safety. There is no need to check blood pressure every 10 minutes; in fact, doing so may increase the patient's discomfort. Reducing fiber intake would not normalize the patient's blood glucose levels.

Liberation

- Drug released from dosage form and is dissolved in body fluid - Process of converting oral drug can be influenced by food and water in the stomach

Which stage of new drug development involves giving the medication to large numbers of individuals with the disorder that the medication intends to treat?

- Developmental stage—Phase 3 - If phase 1 trials are successful, the drug is moved to phase 2, which involves a smaller population of patients who have the condition that the drug is designed to treat. Studies at various dosages are conducted to determine the success rate and safety of a drug for its intended use. If successful, the drug is advanced to phase 3 trials, in which larger patient populations are used to ensure the statistical significance of the results. Studies in this phase also provide additional information on proper dosing and safety. Phase 1 studies are done to determine an experimental drug's pharmacologic properties, safe dosage range, potential for toxicity at a certain dosage, and safe routes of administration. The study population consists of either normal volunteers or the intended treatment population, such as those patients who have failed standard treatments of certain cancers or dysrhythmias. Phase 2 studies usually require 20 to 100 subjects, who are treated for 4 to 6 weeks. Studies in this phase are done to determine the success rate of a drug for its intended use. After the manufacturer decides to market the medication, there is ongoing review of adverse effects of the new drug, as well as periodic inspections of the manufacturing facilities and products.

Distribution

- Drugs are transported throughout the body by body fluids to the sites of action - Protein binding and fat solubility affect distribution - Organs with largest blood supply receive the distributed drug most rapidly - Some drugs cannot pass through the blood-brain barrier or the placental barrier

Excretion

- Elimination of drug metabolites and some of the active drug from the body - Kidneys are the major organ of excretion; some excreted in feces

Which form of medication is more easily administered for a toddler who requires a course of antibiotics? a) Enteric b) Capsules c) Tablets d) Liquid

D) Liquid Rationale: Very small children are not able to swallow solids such as tablets or capsules. They should receive medications carefully measured in a calibrated dropper or oral syringe.

Displacement (Table 2-1)

The displacement of the first drug from protein-binding sites (i.e. bound drugs are inactive) by a second drug increases the activity of the first drug because a more unbound drug is available . (i.e. warfarin + valproic acid = increased anticoagulant effect)

Incompatibility (Table 2-1)

The first drug is chemically incompatible with second drug, thereby causing deterioration when the drugs are mixed in the same syringe or solution or are administered together at the same site; signs include haziness, formation of a precipitate, or a change in color of the solution when the drugs are mixed (i.e. ampicillin + gentamicin = ampicillin inactivates gentamicin )

Due to the decreased protein-binding capacity in preterm infants, what adjustment in dosage of protein-binding drugs would need to made? a) The dosage should be decreased. b) The dosage should be increased. c) The dosage should be kept at the same level. d) Protein-binding drugs are not administered to infants.

b) The dosage should be increased. Rationale: Drugs that are relatively insoluble are transported in the bloodstream bound to plasma proteins (albumin and globulins). There is a decreased affinity for binding in infants, especially preterm infants. These drugs are then distributed over a wider area of the neonate's body. They will therefore require a higher dosage of these medications in order to achieve a therapeutic effect.

When the nurse administers a 50-mg dose of a drug with a half-life of 6 hours, how many milligrams will remain in the body at 24 hours? a) 25 mg b) 12.5 mg c) 6.25 mg d) 3.13 mg e) 1.56 mg

d) 3.13 mg Rationale: The half-life of a drug is the time required for 50% of the drug to be eliminated from the body. In this example at 24 hours, 6.25% or 3.13 mg of the drug would remain in the body.

Which route of administration has the fastest rate of distribution? a) Subcutaneous b) Intramuscular c) Transcutaneous d) Intravenous

d) Intravenous

Interference (Table 2-1)

the first drug inhibits the metabolism or excretion of the second drug, thereby causing increased activity of the second drug. (i.e. probeneacid + ampicillin = prolonged antibacterial activity of ampicillin because probenecid blocks the renal excertion of ampicillin)

Metabolism

- The process whereby the body inactivates drugs - Primary organ of metabolism is the liver; other sites are GI tract and lungs

Three reasons for obtaining a drug history

- To evaluate need for medication - To obtain current and past use of over-the-counter medication - To identify problems related to drug therapy

verbal orders

- Verify and Repeat - should be avoided as much as possible - Physician must cosign and date the order within 24 hours (applies to verbal and telephone orders).

Tertiary sources include (for assessment):

- literature to provide background information - diagnostic tests - diet

Pharmacogenetics

- study of how drug response may vary according to inherited differences - Significant differences can occur among racial and ethnic groups

Synergistic effect (Table 2-1)

- the combined effects of two drugs is greater than the sum of the effect of each drug given together (i.e. aspirin + codeine = much greater analgesic effect) - Effect resulting from two drugs acting synergistically; the effect of the two drugs combined is greater than the effect that would be expected if the individual effects of the two drugs acting alone were added together.

Electronic transmission of patient orders

Fax or computerized provider order entry (CPOE).

Which piece of information obtained during a patient assessment is a subjective finding? a) Patient states, "I have pain in my abdomen." b) Temperature of 38.5º C c) 400 mL of clear, yellow urine d) Blood pressure of 116/74 mm Hg

Answer: a Rationale: A subjective finding is one which the nurse makes using physiologic parameters. A patient's report of pain is a subjective finding because people experience pain differently. An objective assessment is clearly measurable and consistently reportable.

The nurse is preparing a patient for discharge after a surgical procedure. Which method is best for teaching the patient about his or her prescribed drugs? a) Prescription blank handwritten by the physician b) Magazine ads featuring the prescribed medications c) Verbal explanations along with drug summary sheets d) Unit-dose packages from this morning's medications

Answer: c Rationale: Typically, verbal explanations are best as long as the patient is able to hear adequately. Drug summary sheets are prepared at a reading level appropriate for most people. Prescription forms are not a good teaching tool for medications; patients typically don't get to keep prescription forms after filling them at the pharmacy. Unit-dose packages are inappropriate because they may not represent the same manufacturer of the drugs that the patient will be taking, which may lead to confusion.

An older adult patient is being prepared for discharge after experiencing a stroke with some residual damage. The patient and family are scheduled to receive a large amount of information from the nurse regarding proper care and safety at home. What is the nurse's best course of action? a) Present the patient and family with all of the information a few days before discharge. b) Present the patient and family with all of the information the day before discharge. c) Break the teaching content down into manageable sections and present them individually in the days before discharge. d) Have a home health nurse teach the patient and family at home a week after discharge.

Answer: c Rationale: Discharge teaching is an ongoing process and should not wait until the patient is ready to go home. The patient and family need to learn about home care before discharge, and the content should be presented in small sections and repeated as necessary because repetition enhances learning. The patient's readiness to learn and educational level also must be taken into consideration.

The nurse is supposed to perform postoperative teaching for a patient who is scheduled to be discharged the next day. The patient appears fatigued, in pain, and irritable. The nurse knows that there will be little time for teaching on the day of discharge. What is the nurse's best course of action? a) Deliver the teaching now because there won't be enough time tomorrow. b) Allow the patient to nap, and return to perform the teaching in one hour. c) Teach the family member who is present, so he or she can share the information with the patient after discharge. d) Determine the patient's need for analgesia and rest, and return to perform the teaching after the patient feels better.

Answer: d Rationale: After the patient's basic needs are assessed and met, he or she will be better able to focus on the educational material and be prepared for discharge. It is important for the patient to verbally demonstrate learning as well as perform any skill autonomously.

The main advantage of using barcode scanning devices is: a) allowing nurses to scan a patient's name band without reading it. b) being the sole means of maintaining safety in drug administration. c) causing increase in medication errors in the institutions using this technology. d) being the final safety check after the nurse has verified essential information.

Answer: d Rationale: Computerized handheld devices are gaining in popularity due to their ability to decrease the medication error rate in hospitals. The nurse holds the primary responsibility to see that patients receive the proper medications.

Which is an independent nursing action? a) Orders medications based on the patient's medical diagnosis b) Orders laboratory tests depending on the medications ordered c) Chooses an alternate route for medications if indicated d) Verifies the correct route of medication administration

Answer: d Rationale: Verification of the correct route of administration is an independent nursing action that is required as part of the "six rights" of administration. Ordering drugs or labs and changing a route of administration are not within the scope of practice for a nurse.

Which patient has the greatest percentage of body water? a) Older adult b) Middle-aged person c) Infant d) Toddler

C) infant Rationale: An infant has a total body water percentage of 74%, whereas a premature infant has an even higher percentage at 83%. As we age, our total percentage of body water decreases and our percentage of total body fat increases.

All drugs are processed in the body through pharmacokinetics. What is the correct order that drugs pass through the body? a) Absorption, distribution, metabolism, excretion b) Distribution, metabolism, absorption, excretion c) Biotransformation, distribution, absorption, excretion d) Excretion, distribution, absorption, metabolism

a) Absorption, distribution, metabolism, excretion

How does a nursing diagnosis differ from a medical diagnosis? a) A nursing diagnosis concerns a disease that impairs physiologic function. b) A nursing diagnosis evaluates a patient's response to actual or potential health problems. c) A nursing diagnosis determines the rate of Medicare reimbursement. d) A nursing diagnosis does not consider potential future problems.

b) A nursing diagnosis evaluates a patient's response to actual or potential health problems. Rationale: A nursing diagnosis takes the form of a three-part statement relating to a patient's response to actual or potential health problems and life processes. It is constantly changing, whereas a medical diagnosis is frequently unchanged during a patient's hospitalization.

A patient reports postoperative pain, and the nurse administers morphine (a narcotic analgesic) intravenously to ease the pain. Fifteen minutes later, the nurse notes that the patient is very drowsy, respirations are slow and shallow, and oxygen saturation is low. The nurse administers another drug that decreases the action of the morphine. What is this effect called? a) Displacement b) Antagonistic c) Interference d) Synergistic

b) Antagonistic

What is the foundation for the clinical practice of nursing? a) Assessment b) Nursing process c) Planning d) Evaluation e) Implementation

b) Nursing process

Which type of topical drug is more readily absorbed by infants? a) Fat-soluble b) Water-soluble c) Emollient d) Protective

b) Water-soluble Rationale: Topical administration with percutaneous absorption is usually quite effective in infants because the outer layer of skin is not fully developed. Because the skin is more fully hydrated at this age, water-soluble drugs are absorbed more readily.

The nurse is preparing to teach a postsurgical patient who has a new colostomy about proper colostomy care. The patient says, "Just show me how to do it; let me try, and I'll learn what to do." Which domain of learning is indicated by this statement? a) Cognitive b) Affective c) Psychomotor d) Determined

c) Psychomotor Rationale: The patient's willingness to see, hear, and do indicates a learning style in the psychomotor, or "doing" domain. Demonstration of the skill with a step-by-step, hands-on approach is usually the best way for this type of learner to be trained in a new skill.

A clinical judgment that a person is more susceptible to a particular problem than others in the same situation is defined as which type of nursing diagnosis? a) Actual b) Wellness c) Risk/high risk d) Syndrome

c) Risk/high risk Rationale: A risk/high-risk nursing diagnosis is supported by risk factors that increase a patient's vulnerability beyond that of the same population. The patient can be at risk or at high risk for a particular problem.

It is important to maintain therapeutic levels of drugs to avoid the complications of being over- or undermedicated. If a drug level of 0.5 to 2 ng/mL is considered therapeutic, a drug level of 0.45 ng/mL is considered to be what? a) Toxic b) Therapeutic c) Subtherapeutic d) Tolerant

c) Subtherapeutic Rationale: Drugs are therapeutic when maintained within the normal range for the drug. In this example, the level is below that indicated for the drug, or subtherapeutic. A subtherapeutic level would require increasing the dose for the patient to achieve the maximum benefit of the drug.

Primary source (for assessment)

is produced by the patient