1
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
Midterm Outline
Chapter 1:
The Role of the Advanced Practice Nurse as Prescriber
Roles and responsibilities of APRN prescribers: APRNs exist in a range of practices and include
certified RN anesthetists, certified nurse midwives, and others whose title includes the words
nurse practitioner or advanced practice registered nurse. The responsibility for the final decision
on which drug to use and how to use it is in the hands of the APRN prescriber. The degree of
autonomy in this role and the breadth of drugs that can be prescribed vary from state to state
based on the nurse practice act of that state. Every year, the January issue of the Nurse
Practitioner journal and an issue of the American Journal for Nurse Practitioners present a
legislative update providing a summary of each state's practice acts as they relate to titling, roles,
and prescriptive authority.
As of January 2015, the following were true of NP regulation of practice and prescribing
authority:
• All states have title protection for NPs.
• Only Oregon has mandated third-party reimbursement parity for NP services.
• In all but five states, the control of practice and licensure is within the sole authority of the
state's board of nursing. These five states have joint control in the board of nursing and the board
of medicine. • Scope of practice is determined by the individual NP's license under the nurse
practice act of the licensing jurisdiction. Some have a graduated scope based on experience level.
New prescribers need to understand that their employment sites may restrict this legal scope of
practice but cannot extend it.
• In 17 states and the District of Columbia, NPs have independent scope of practice and
prescriptive authority without a requirement or attestation for physician collaboration,
consultation, delegation, or supervision.
• Six states have full autonomous practice and prescriptive authority following a period of
postlicensure/postcertification supervision or collaboration.
The 2010 Institute of Medicine's publication Future of Nursing:
Leading Change, Advancing Health called for removing scope of practice barriers and allowing
NPs to practice to the full extent of their education and training. Many states are responding to
this call, with the expectation that the above list will be significantly modified in years to come.
Clinical judgement in Prescribing: Prescribing a drug results from clinical judgment based on
a thorough assessment of the patient and the patient's environment, the determination of medical
and nursing diagnoses, a review of potential alternative therapies, and specific knowledge about
the drug chosen and the disease process it is designed to treat. In general, the best therapy is the
least invasive, least expensive, and least likely to cause adverse reactions. Frequently, the best
choice is to have lifestyle, nonpharmacological, and pharmacological therapies working together.
When the choice of treatment options is a drug, several questions arise.
Collaboration with other providers: No one member of the health-care team can provide high-
quality care without collaborating with other team members. They most often collaborate with
, 2
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
physicians, pharmacists, podiatrists, mental health specialists, therapists, and other providers,
including APRNs who are not NPs, physician assistants, and other nurses.
Autonomy and Prescriptive authority: The growth in autonomy and prescriptive authority for
NPs and other APRNs is a source of pride. APRNs have now successfully overcome the “cannot
prescribe,” “cannot diagnose and treat,” and “cannot admit” prohibitions to practice that have
required so much time and energy to overturn in the past. More states are broadening and
expanding the legal, reimbursement, and prescriptive authority to practice for all APRNs,
including NPs. By January 2004, all states had recognized the NP title, scope of practice, and
prescriptive authority in legislation. Momentum to full autonomy is gaining, with 26 states
allowing independent practice for NPs and 21 states allowing independent full prescribing as of
January 2015. APRNs in other states have also gained recognition, although the scope of practice
and prescriptive authority is often more restricted. These gains are not written in stone, however,
and can be reversed. Despite continuing research studies that demonstrate the effectiveness of the
role of the APRN in improving patient outcomes, barriers remain. Major concerns related to
prescriptive authority must continue to be addressed. Not all states have legislation that permits
APRNs to prescribe independently of any required physician involvement. Turf battles continue
between APRNs and physicians at national and many state levels over physician supervision
requirements and co-signatures on prescriptions. The advent of the Doctor of Nursing practice
degree with its comparable level of education to that of other health-care providers and a focus
on independent practice may address some of these issues about supervision. However, the
American Medical Association continues to stress the need for physician supervision and final
authority for the patient, even for APRNs who hold the DNP. This push for physician control
occurs despite data from malpractice and malfeasance ratios that clearly show that the rationale
for physician supervision is unfounded.
Chapter 2: Review of Basic Principles of Pharmacology
Metabolism: Metabolism & Half Life: The rate of drug metabolism depends on the blood
levels of drug in relation to the affinity of the drug for its metabolism enzymes. Most drugs are
present at concentrations below their Km for metabolism (the concentration at which metabolism
is half of maximum). Under these conditions, metabolism is related to drug concentration so that
a fixed fraction of drug is metabolized per hour. This is called first-order metabolism and is
characterized by a half-life, the time period over which the drug concentration will decrease by
half. So, blood levels decrease 50% in one half-life, 75% in two half-lives, and 87.5% in three
half-lives. As a general rule, drugs tend to be administered at dosing intervals that are close to
their half-life. Some drugs—ethanol is the prototype—are present at concentrations well above
their Km for metabolism. When this happens, enzymes act near to their maximal metabolic
capacity and metabolize a constant amount of drug each hour. This is called zero-order
metabolism. Rarely but importantly, some drugs are present at blood concentrations that range
from below to above the Km for their metabolism. At lower doses or concentrations, they are
metabolized like typical drugs, but at higher doses or concentrations their metabolism is limited.
Phenytoin is a prototypical example of a drug with “mixed-order” or Michelis-Menten,
pharmacokinetics. Above a certain level of phenytoin dosing (about 300 mg/day in adults),
dosage must be adjusted by small amounts, which can produce disproportional increases in blood
levels as metabolism changes from first order to zero order.
, 3
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
Drug Responses: Homeostasis is the tendency of a cell, tissue, or the body not to respond to
drugs but instead to maintain the internal environment by adjusting physiological processes.
Before a medication can produce a response, it often must overcome homeostatic mechanisms.
Drug effects depend on the amount of drug that is administered. If the dose is below that needed
to produce a measurable biological effect, then no response is observed; any effects of the drug
are not sufficient to overcome homeostatic capabilities. If an adequate dose is administered, there
will be a measurable biological response. With an even higher dose, we may see a greater
response. At some point, however, we will be unwilling to increase the dosage further, either
because we have already achieved a desired or maximum response or because we are concerned
about producing additional responses that might harm the patient. Because pharmacology is the
study of substances that produce biological responses, measurement of what happens when we
administer medications is important. We will need ways to express and compare drug activity so
that we can describe the action or effect of drugs, compare the effects of different drugs, and
predict their pharmacological effects.
Receptors: Agonists, antagonists:
Drugs can do three basic things once they bind to a receptor.
• Agonists, or full agonists, are drugs that produce receptor stimulation and a
conformational change every time they bind. Full agonists do not need all of the available
receptors to produce a maximum response. Some agonists can produce their maximum
response by binding to less than 10% of the available receptors. The receptors that are left
over and not needed for a response are called spare receptors.
• are drugs that occupy receptors without stimulating them. Antagonists occupy a receptor
site and prevent other molecules, such as agonists, from occupying the same site and
producing a response. Antagonists produce no direct response. The response we see
following administration of antagonists results from their inhibiting receptor stimulation
by agonists.
For example, beta blockers such as propranolol and atenolol act as antagonists at the beta-
adrenoceptor.
Adrenergic nerve activity can raise heart rate, and patients with high heart rates experience a
significant drop in heart rate following administration of beta blockers. The same administration
may have little effect on patients who lack adrenergic nerve activity and already have a lower
heart rate. The effect of antagonists is dependent on the background receptor activity that it can
block. Antagonists produce a shift in the concentration-effect relationship for agonists acting at
that same specific receptor as the antagonist; they make agonists for the same receptor appear
less potent. The effect of an antagonist is dependent on its blood levels and its affinity for the
receptor. Most antagonists in clinical use are competitive reversible antagonists, and it is possible
to overcome the antagonist effects with higher concentrations of the competing agonist. A very
small number of antagonist drugs (e.g., echothiophate, phenoxybenzamine) act by irreversibly
binding to the receptor; their antagonism remains until new receptors can be produced by the
cell.
Partial agonists are drugs that have properties in between those of full agonists and
antagonists. Partial agonists bind to receptors but when they occupy the receptor sites, they
stimulate only some of the receptors. This is sometimes called intrinsic activity. So they can act
, 4
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
as part agonist and part antagonist. Partial agonists would require all of the available receptors to
produce their full response, and the maximum response for a partial agonist is less than that for a
full agonist.
The beta blockers acebutolol, penbutolol, and pindolol are partial agonists. Administration can
block the effects of adrenergic nerves on heart rate, but partial agonist activity keeps heart rate
from falling too low, as might occur following administration of a pure beta-adrenoceptor
antagonist. So beta blockers with intrinsic sympathomimetic activity control heart rate within a
range that is higher than the response to an antagonist and lower than the response to an agonist.
Pharmacokinetics: Absorption:
Medications produce little clinical effect when they remain inside the prescription bottle. To
produce a biological effect, drugs must enter the body. Once inside the body, drugs can interact
with various receptor molecules to produce physiological changes that result in clinical
effectiveness. The way in which medications are presented to the body affects the speed, the
extent, and the duration of drug absorption. The route of administration also affects patient
compliance, that is, their willingness to follow recommendations for taking a medication. So
choosing the route of administration can have important implications for drug therapy, and it is
not surprising that a variety of routes of administration can be chosen based on the chemical
properties of an individual drug, the condition of an individual patient, and the goal of drug
treatment. There is more to it than just having a medication enter the body. Patients can swallow
a poorly formulated dosage form that travels through the intestines and arrives unchanged in the
toilet. There is little biological effect from these “bedpan bullets” if the active medication never
reaches its site of action.
Distribution:
After a drug is absorbed, it still must reach its site of action to produce an effect. The process of
drugs moving throughout the body is called distribution. Distribution of drugs can occur by
transfer through the bloodstream and passive diffusion, or their distribution can be promoted or
limited by the presence of transport systems that may selectively transport or exclude drugs
based on size, charge, or chemical structure. Diffusion can influence the action of drugs; drugs
can be effective only if they reach their site of action in adequate concentrations before they are
metabolized.
Protein Binding:
Drugs passively diffuse and distribute when they are unbound and uncharged. Drugs can bind to
a variety of proteins that are present in the bloodstream. These are often called plasma proteins.
Many plasma proteins are produced in the liver, and their presence in the blood reflects liver
function, nutritional status, and the effect of aging and disease.
• Albumin is a major protein in the blood and is measured as part of a typical blood
analysis. Albumin has a molecular weight of 66,500 and is too large to be excreted by the
kidneys in healthy patients, although in renal disease albumin is lost in the urine.
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
Midterm Outline
Chapter 1:
The Role of the Advanced Practice Nurse as Prescriber
Roles and responsibilities of APRN prescribers: APRNs exist in a range of practices and include
certified RN anesthetists, certified nurse midwives, and others whose title includes the words
nurse practitioner or advanced practice registered nurse. The responsibility for the final decision
on which drug to use and how to use it is in the hands of the APRN prescriber. The degree of
autonomy in this role and the breadth of drugs that can be prescribed vary from state to state
based on the nurse practice act of that state. Every year, the January issue of the Nurse
Practitioner journal and an issue of the American Journal for Nurse Practitioners present a
legislative update providing a summary of each state's practice acts as they relate to titling, roles,
and prescriptive authority.
As of January 2015, the following were true of NP regulation of practice and prescribing
authority:
• All states have title protection for NPs.
• Only Oregon has mandated third-party reimbursement parity for NP services.
• In all but five states, the control of practice and licensure is within the sole authority of the
state's board of nursing. These five states have joint control in the board of nursing and the board
of medicine. • Scope of practice is determined by the individual NP's license under the nurse
practice act of the licensing jurisdiction. Some have a graduated scope based on experience level.
New prescribers need to understand that their employment sites may restrict this legal scope of
practice but cannot extend it.
• In 17 states and the District of Columbia, NPs have independent scope of practice and
prescriptive authority without a requirement or attestation for physician collaboration,
consultation, delegation, or supervision.
• Six states have full autonomous practice and prescriptive authority following a period of
postlicensure/postcertification supervision or collaboration.
The 2010 Institute of Medicine's publication Future of Nursing:
Leading Change, Advancing Health called for removing scope of practice barriers and allowing
NPs to practice to the full extent of their education and training. Many states are responding to
this call, with the expectation that the above list will be significantly modified in years to come.
Clinical judgement in Prescribing: Prescribing a drug results from clinical judgment based on
a thorough assessment of the patient and the patient's environment, the determination of medical
and nursing diagnoses, a review of potential alternative therapies, and specific knowledge about
the drug chosen and the disease process it is designed to treat. In general, the best therapy is the
least invasive, least expensive, and least likely to cause adverse reactions. Frequently, the best
choice is to have lifestyle, nonpharmacological, and pharmacological therapies working together.
When the choice of treatment options is a drug, several questions arise.
Collaboration with other providers: No one member of the health-care team can provide high-
quality care without collaborating with other team members. They most often collaborate with
, 2
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
physicians, pharmacists, podiatrists, mental health specialists, therapists, and other providers,
including APRNs who are not NPs, physician assistants, and other nurses.
Autonomy and Prescriptive authority: The growth in autonomy and prescriptive authority for
NPs and other APRNs is a source of pride. APRNs have now successfully overcome the “cannot
prescribe,” “cannot diagnose and treat,” and “cannot admit” prohibitions to practice that have
required so much time and energy to overturn in the past. More states are broadening and
expanding the legal, reimbursement, and prescriptive authority to practice for all APRNs,
including NPs. By January 2004, all states had recognized the NP title, scope of practice, and
prescriptive authority in legislation. Momentum to full autonomy is gaining, with 26 states
allowing independent practice for NPs and 21 states allowing independent full prescribing as of
January 2015. APRNs in other states have also gained recognition, although the scope of practice
and prescriptive authority is often more restricted. These gains are not written in stone, however,
and can be reversed. Despite continuing research studies that demonstrate the effectiveness of the
role of the APRN in improving patient outcomes, barriers remain. Major concerns related to
prescriptive authority must continue to be addressed. Not all states have legislation that permits
APRNs to prescribe independently of any required physician involvement. Turf battles continue
between APRNs and physicians at national and many state levels over physician supervision
requirements and co-signatures on prescriptions. The advent of the Doctor of Nursing practice
degree with its comparable level of education to that of other health-care providers and a focus
on independent practice may address some of these issues about supervision. However, the
American Medical Association continues to stress the need for physician supervision and final
authority for the patient, even for APRNs who hold the DNP. This push for physician control
occurs despite data from malpractice and malfeasance ratios that clearly show that the rationale
for physician supervision is unfounded.
Chapter 2: Review of Basic Principles of Pharmacology
Metabolism: Metabolism & Half Life: The rate of drug metabolism depends on the blood
levels of drug in relation to the affinity of the drug for its metabolism enzymes. Most drugs are
present at concentrations below their Km for metabolism (the concentration at which metabolism
is half of maximum). Under these conditions, metabolism is related to drug concentration so that
a fixed fraction of drug is metabolized per hour. This is called first-order metabolism and is
characterized by a half-life, the time period over which the drug concentration will decrease by
half. So, blood levels decrease 50% in one half-life, 75% in two half-lives, and 87.5% in three
half-lives. As a general rule, drugs tend to be administered at dosing intervals that are close to
their half-life. Some drugs—ethanol is the prototype—are present at concentrations well above
their Km for metabolism. When this happens, enzymes act near to their maximal metabolic
capacity and metabolize a constant amount of drug each hour. This is called zero-order
metabolism. Rarely but importantly, some drugs are present at blood concentrations that range
from below to above the Km for their metabolism. At lower doses or concentrations, they are
metabolized like typical drugs, but at higher doses or concentrations their metabolism is limited.
Phenytoin is a prototypical example of a drug with “mixed-order” or Michelis-Menten,
pharmacokinetics. Above a certain level of phenytoin dosing (about 300 mg/day in adults),
dosage must be adjusted by small amounts, which can produce disproportional increases in blood
levels as metabolism changes from first order to zero order.
, 3
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
Drug Responses: Homeostasis is the tendency of a cell, tissue, or the body not to respond to
drugs but instead to maintain the internal environment by adjusting physiological processes.
Before a medication can produce a response, it often must overcome homeostatic mechanisms.
Drug effects depend on the amount of drug that is administered. If the dose is below that needed
to produce a measurable biological effect, then no response is observed; any effects of the drug
are not sufficient to overcome homeostatic capabilities. If an adequate dose is administered, there
will be a measurable biological response. With an even higher dose, we may see a greater
response. At some point, however, we will be unwilling to increase the dosage further, either
because we have already achieved a desired or maximum response or because we are concerned
about producing additional responses that might harm the patient. Because pharmacology is the
study of substances that produce biological responses, measurement of what happens when we
administer medications is important. We will need ways to express and compare drug activity so
that we can describe the action or effect of drugs, compare the effects of different drugs, and
predict their pharmacological effects.
Receptors: Agonists, antagonists:
Drugs can do three basic things once they bind to a receptor.
• Agonists, or full agonists, are drugs that produce receptor stimulation and a
conformational change every time they bind. Full agonists do not need all of the available
receptors to produce a maximum response. Some agonists can produce their maximum
response by binding to less than 10% of the available receptors. The receptors that are left
over and not needed for a response are called spare receptors.
• are drugs that occupy receptors without stimulating them. Antagonists occupy a receptor
site and prevent other molecules, such as agonists, from occupying the same site and
producing a response. Antagonists produce no direct response. The response we see
following administration of antagonists results from their inhibiting receptor stimulation
by agonists.
For example, beta blockers such as propranolol and atenolol act as antagonists at the beta-
adrenoceptor.
Adrenergic nerve activity can raise heart rate, and patients with high heart rates experience a
significant drop in heart rate following administration of beta blockers. The same administration
may have little effect on patients who lack adrenergic nerve activity and already have a lower
heart rate. The effect of antagonists is dependent on the background receptor activity that it can
block. Antagonists produce a shift in the concentration-effect relationship for agonists acting at
that same specific receptor as the antagonist; they make agonists for the same receptor appear
less potent. The effect of an antagonist is dependent on its blood levels and its affinity for the
receptor. Most antagonists in clinical use are competitive reversible antagonists, and it is possible
to overcome the antagonist effects with higher concentrations of the competing agonist. A very
small number of antagonist drugs (e.g., echothiophate, phenoxybenzamine) act by irreversibly
binding to the receptor; their antagonism remains until new receptors can be produced by the
cell.
Partial agonists are drugs that have properties in between those of full agonists and
antagonists. Partial agonists bind to receptors but when they occupy the receptor sites, they
stimulate only some of the receptors. This is sometimes called intrinsic activity. So they can act
, 4
NR 508 / NP-NR 508 -Pharm Midterm Outline + chart
as part agonist and part antagonist. Partial agonists would require all of the available receptors to
produce their full response, and the maximum response for a partial agonist is less than that for a
full agonist.
The beta blockers acebutolol, penbutolol, and pindolol are partial agonists. Administration can
block the effects of adrenergic nerves on heart rate, but partial agonist activity keeps heart rate
from falling too low, as might occur following administration of a pure beta-adrenoceptor
antagonist. So beta blockers with intrinsic sympathomimetic activity control heart rate within a
range that is higher than the response to an antagonist and lower than the response to an agonist.
Pharmacokinetics: Absorption:
Medications produce little clinical effect when they remain inside the prescription bottle. To
produce a biological effect, drugs must enter the body. Once inside the body, drugs can interact
with various receptor molecules to produce physiological changes that result in clinical
effectiveness. The way in which medications are presented to the body affects the speed, the
extent, and the duration of drug absorption. The route of administration also affects patient
compliance, that is, their willingness to follow recommendations for taking a medication. So
choosing the route of administration can have important implications for drug therapy, and it is
not surprising that a variety of routes of administration can be chosen based on the chemical
properties of an individual drug, the condition of an individual patient, and the goal of drug
treatment. There is more to it than just having a medication enter the body. Patients can swallow
a poorly formulated dosage form that travels through the intestines and arrives unchanged in the
toilet. There is little biological effect from these “bedpan bullets” if the active medication never
reaches its site of action.
Distribution:
After a drug is absorbed, it still must reach its site of action to produce an effect. The process of
drugs moving throughout the body is called distribution. Distribution of drugs can occur by
transfer through the bloodstream and passive diffusion, or their distribution can be promoted or
limited by the presence of transport systems that may selectively transport or exclude drugs
based on size, charge, or chemical structure. Diffusion can influence the action of drugs; drugs
can be effective only if they reach their site of action in adequate concentrations before they are
metabolized.
Protein Binding:
Drugs passively diffuse and distribute when they are unbound and uncharged. Drugs can bind to
a variety of proteins that are present in the bloodstream. These are often called plasma proteins.
Many plasma proteins are produced in the liver, and their presence in the blood reflects liver
function, nutritional status, and the effect of aging and disease.
• Albumin is a major protein in the blood and is measured as part of a typical blood
analysis. Albumin has a molecular weight of 66,500 and is too large to be excreted by the
kidneys in healthy patients, although in renal disease albumin is lost in the urine.
