Pharma Week 1-5
Pharma Week 1-5
Pharma Week 1-5
PHARMACOLOGY
is the study of drugs and its origin, chemical structure, Chinese o Recorded the Pen Tsao (Great Herbal) –
preparation, administration, action, metabolism, and a 40volume compendium of plant remedies dating to
excretion. 2700 B.C.
The study of drugs that alter functions of living
organisms. Egyptians o Archives of remedies on a document
known as Erb’s Papyrus in 1500 B.C.
PHARMACY
o art of preparing, compounding, and dispensing Pharmacologia sen Manuductio and Materia
drugs. It also refers to the place where drugs Medicum
are prepared and dispensed. o First recorded reference to the word
PHARMACIST pharmacology
o a person licensed to prepare and dispense
drugs to make up prescriptions. Early 1800s o Chemists isolates specific
substances from complex mixtures
BRANCHES OF PHARMACOLOGY o Pharmacologists then study their effects in
The branch of pharmacology concerned with animals
mechanisms of drug action and the relationships o Fredrich Serturner (first isolated morphine
between drug concentration and responses in the body. from opium, injected himself and three other
friends with huge doses (100mg))
Pharmacodynamics o Pharmaco means
“medicine” dynamic means BASIC CONCEPTS OF PHARMACOLOGY
“change”. DRUGS
o Refers to how a medicine changes the body. o are chemicals that alter physiochemical
processes in body cells. o They can
Pharmacokinetic o Kinetic means “movement or stimulate or inhibit normal cellular functions. o
motion”. Used interchangeably with medicines.
o The study of drug movement throughout the
body.
o How the body deals with medications.
o Actions and side effects of medications in
patient.
Pharmacognosy
o The branch of knowledge concerned with
medicinal drugs obtained from plants or other
natural resources.
Pharmacotherapeutics
o The study of the therapeutics uses and effects
of drugs.
o Beneficial and adverse effects of drugs. TYPES OF DRUG NAMES
DRUG NAMES DEFINITION EXAMPLE
Pharmacovigilance Generic or name approved Paracetamol
o The practice of monitoring the effects of Nonproprietary by the Medical or
medical drugs after they have been licensed for
Name Pharmaceutical
use especially in order to identify and evaluate
Associations in
previously unreported adverse reaction.
the original
country of
Toxicology o The branch of science concerned
manufacture and
with the nature, effects, and detection of poisons. o
is adopted by all
The measurement and analysis of potential toxins,
countries.
intoxicating or banned substances, prescription
Brand name or name given by Adol
medications present in a person’s body.
trade name the manufacturer Panadol
of the drug. Biogesic
HISTORY OF PHARMACOLOGY
Babylonians
Chemical name name that Acetaminophen
o Earliest surviving “prescriptions” on clay tablets
describes the
in 3000 B.C.
atomic or
chemical
structure.
B. Liquid Form
PHASE I 1. Syrup
o chemicals cleared for human testing, there 2. Suspension
are significant therapeutic benefits. o 3. Elixir
testing done on healthy male 4. Emulsion
subjects o companies begin 5. Inhalants
developing a brand
name C. Topical Forms
1. Cream
ORPHAN DRUG 2. Ointment
o are chemicals that are discarded Phase I 3. Lotion
o will not participate in the next phase 4. Patch
criteria: 5. Gels
• lack therapeutic activity in
humans
• too toxic PRINCIPLES OF DRUG ADMINISTRATION
• produce unacceptable side MEDICATIONS
effects o Are substances administered for the diagnosis,
• teratogenic cure, treatment, or relief of symptom or
prevention of disease
PHASE II
o chemicals cleared for limited clinical PRACTICE GUIDELINES
studies o RNs are responsible for own actions, illegible
o some may not further proceed with the order should be questioned or clarified
evaluation due to the following criteria o RNs should be knowledgeable about the
• less effective than expected medication
• are too toxic o If the RN is uncertain about the calculation, ask
another nurse to double check
TERMINOLOGIES:
Drug Name
o The systematic naming of drug used in
Pharmacology
Topical Medication
o a drug suitable for administration applied to a
particular body part most often applied to
surfaces such as skin and mucous membrane.
Onset
o is the time it takes for a drug to reach the
minimum effective concentration (MEC) after
administration. o Time from drug
administration to first observable effect (T0-T1)
Dose – Response Relationship o Is the body’s
physiological response to change in drug concentration
Peak
at the site of action.
o occurs when it reaches its highest
concentration in the blood/plasma
Potency
concentration. (T0-T2)
o Refers to the amount of drug needed to elicit a
specific physiological response to drug. Duration of Action o is the length of time the drug
exerts a therapeutic effect. period from onset until the
Efficacy o magnitude of effect a drug can cause
drug effect is no longer seen. (T1-T3)
when exerting its maximal effect.
Peak
o highest plasma concentration. 30 minutes after
infusion.
PARAMETERS OF DRUG ACTION
Trough
Therapeutic Index – (TI) o describes the o lowest plasma concentration. 30 minutes prior
relationship between the therapeutic dose of a drug to the next infusion.
(ED50) and the toxic dose of a drug (TD50)
THEORIES OF DRUG ACTION
A. Drug-Receptor Interaction o Certain portion of
drug molecule (active site) selectively combines with
some molecular structure (reactive site) on the cell
to produce a biologic effect.
Drug Response
Drug Response may be:
a. Primary o
always
desirable/physiologic
effects
b. Secondary o desirable or undesirable
o Ex: Diphenhydramine
(Benadryl)
PHAMACOKINETICS
Is the process of drug movement throughout Movement of drug particles from GIT to body fluids
the body that is necessary to achieve drug involve 3 processes:
action.
1) Passive transport
Diffusion – drugs move across the cell
membrane from an area of higher
concentration to one of lower
concentration.
2) Facilitated diffusion
Active transport – requires a carrier such as
enzyme or protein to move the drug against a
concentration gradient. Energy is required. 3)
Pinocytosis
is the process by which cells carry a drug across
PROCESSES their membrane by engulfing the drug particles in a
Mnemonic “ LAD ME” vesicle.
1. L=
LIBERATION
The release of the drug from it’s dosage form.
Is the first step in the process by which
medication enters the body and liberates the
active ingredient that has been administered.
The pharmaceutical drug must separate from
the vehicle or the excipient that it was mixed
with during manufacture. Some authors split
the process of liberation into three steps:
disintegration, disaggregation, and dissolution. Factors affecting drug absorption
A limiting factor in the adsorption of Drug solubility o lipid soluble drugs pass
pharmaceutical drugs is the degree to which readily through GI membrane,
they are ionized, as cell membranes are o water- soluble drugs need an enzyme or
relatively impermeable to ionized molecules. protein
The characteristics of a medication's excipient
play a fundamental role in creating a suitable Local condition at site of absorption o weak
environment for the correct absorption of a acids less ionized in stomach o Readily pass
drug. This can mean that the same dose of a
through the small intestine.
drug in different forms can have different
bioequivalence, as they yield different plasma
Pain/stress/solid foods/fatty or hot foods o
concentrations and therefore have different
slows down gastric emptying time
therapeutic effects. Dosage forms with
modified release (such as delayed or extended
release) allow this difference to be usefully 3. D = DISTRIBUTION
applied. The process by which diffuses or is transferred
from intravascular space to extravascular
2. A = ABSORPTION space (body tissue).
Is the movement of the drug into the process by which drug becomes available to
body fluids and tissues.
bloodstream after administration.
is the movement of the drug from the
80% of drugs are taken by mouth – enteral.
circulation to body tissues.
Movement of drug molecules from site of
administration to circulatory system
(Ex. Digoxin)
4. M = METABOLISM
Also known as the Biotransformation Other Sites of Metabolism
is the process by which the body chemically 1) Plasma
changes drugs into a form that can be excreted. 2) Kidneys
3) Membranes of intestines
NURSES RIGHTS WHEN ADMINISTERING MEDICATION The patient’s home safety needs
The nurses’ six Rights: Caregiver needs and support system o
1. Right to complete and clear order. there may be a special support system unique to
2. Right to have the correct drug; the individual .
3. Right to have access to information; o These are persons who may assist in
4. Right to have policies to guide safe medication drug preparation, organizing the pills
administration. and ordering the medications.
5. Right to administer medications safely and to
identify problems in the system; Support systems can:
6. Right to stop, think and be vigilant when o alert the patient to side effects; o
administering meds. encourage compliance; and
o notify the health care
THE NURSING PROCESS: PATIENT – CENTERED provider if a o problem arises.
COLLABORATIVE CARE
Purpose of the Nursing Process (Core of the practice): OBJECTIVE DATA
1. To identify, diagnose, and treat human responses to what the nurse observes about the patient’s health
health and illness status.
2. It supports the nurse in prioritizing safe, timely Involves collecting the patient’s health information
delivery of drug administration. by using the senses: seeing, hearing, smelling and
Careful attention to each phase of the touching.
process promotes It provides information about the patient’s symptoms
the patient’s success with the prescribed and also targets the organs most likely to be
medication regimen. affected by drug therapy.
• Readiness for enhanced Health Management A primary role of the nurse: teaching both patients
• Ineffective Health Management r/t lack of finances and families about drug administration.
Acute pain r/t presence of physical injury secondary to All teachings must be tailored to the patient’s
______ o (i.e. surgery/ educational/ literacy level; and must trust the nurse
abscess) for learning to begin.
Risk for acute confusion r/t the use of a pharmaceutical
agent
• In planning, the nurse uses the data collected to set
goals and expected outcomes and interventions.
Goals or expected outcomes should address the
problems in the patient’s nursing diagnoses. Principles to remember when teaching patients about
drug administration: 1. General
Effective Goal setting has the following qualities: Instruction to take the meds as prescribed.
a. The expected change is realistic, measurable, and Consistency in adhering to the prescribed regimen
includes reasonable deadlines. is important.
b. The goal is acceptable to both patient and nurse. a. Provide simple written instructions
c. The goal is dependent on the patient’s with the doctor, pharmacy names
decisionmaking ability. and phone numbers.
b. Instruct the patient to notify the
NURSING PROCESS: PLANNING Attending Physician (Care
Provider) if any of the following
d. The goal is shared with other health care providers,
occur:
including the family or caregivers.
o Adjustment in the dose,
e. The goal identifies components for evaluation.
frequency or time of the
drug.
1. Identified expected outcomes.
o A female patient
o Example: The patient will independently
becomes pregnant.
administer the prescribed dose of 4 units of
o An OTC supplement is
regular insulin by the end of the fourth
added.
session of instruction.
2. Side effects
2. Explained the need for the medication to the patient
Give instructions that will help minimize
and the significant others.
any side effects.
o Clarify specially if the patient wants to
Example:
selfadminister.
o Avoiding direct sunlight with drugs
3. Plan preparation of medications to avoid
interruptions and distractions. Follow Institutional that can cause
protocol. photosensitivity
o Expected changes in urine or
NURSING PROCESS: IMPLEMENTATION stool color
1. Prepared medications using aseptic technique. o Dizziness caused by orthostatic
2. Arrange medication tray and cups in preparation hypotension: o to rise slowly
area neatly. from a sitting to a standing
3. Prepare medication for ONE PATIENT AT A TIME; position.
followed the RIGHTS OF MEDICATION 3. Self- administration
administration. Ongoing assessment of the patient’s motor
4. Selected the correct drug; compared the name of skills and abilities. Modify the plan as
medication label with the Medication Administration necessary.
Record or medication card. Instruct patient on drug administration
5. Read the label three times: according to the prescribed route. Include
a. upon removing the medicine container a ret dem as appropriate.
from the meds box; Use Drug cards as needed in teaching.
b. before pouring/ removing the contents and
c. before returning to the medication box.
6. Check or recalculate drug dose as necessary.
7. For controlled substances:
o Check record for medication count
and compare with current count /
supply available.
8. Explain to the patient or caregiver each of the
medication’s the purpose, action, schedule and side
effects.
TJC Standard
o Facilities to find out, record and share info AS a rule, do not crush meds with any of the following: To
on any drugs patients are taking, and it crush or not to crush?
requires them to compare that list of drugs CD Controlled delivery CR Controlled release
with a list of any new drugs being given. DR Delayed release ER Extended release
IM Immediate release LA Long acting
DISPOSAL OF MEDICATIONS MR Modified release SA Sustained action /
If no Program is in place: short acting
1. Remove meds from the original package and mix
SR Sustained release TR Timed release
them with unpalatable substances such as dirt, kitty
liter, or used coffee ground ( DO NOT CRUSH TR Timed release XT Extended release
TABS/CAPS). This to make the meds less XR Extended release
attractive to people and animals.
2. Place the mixture in a sealed container; throw in the Refer to the pharmacist when in doubt. Listing:
household trash. Do-Not-Crush-List
3. Scratch out all personal info on the prescription http://www.ismp.org/tools/donotcrush.pdf
label before disposing of the empty container.
HIGH ALERT MEDICATIONS
FDA/DEA/BFAD Can cause significant harm to the patient.
o Issued Guidelines for appropriate disposal. o major effect on the patients organs: cardiac,
respiratory, vascular, and neurologic systems. o
Public/ Private Agencies o Secure, convenient, Also affects the sympathetic and parasympathetic
and responsible methods for collecting and o nervous system.
destroying meds and controlled substances. o High alert meds according to the Institute for Safe
o examples: take-back events, mail-back Medication Practices(ISMP):
programs, collection receptacles • epinephrine, subcutaneous/IV
• methotrexate (non-onco oral use)
Local collection program: • Oxytocin, IV •
o as authorized by the State for disposal of Nitroprusside sodium inj.
medical waste and hazardous materials. • Sodium chloride
• promethazine, IV and others
Sharps Safety o OSHA and Needlestick Safety
and Optimize Safety by:
Prevention Act (NSPA)2000 o + 1. Simplifying storage, preparation and administration.
Nurses Organizations campaigned for the 2. Write policies concerning safe administration.
Protection of the Nursing Staff from work 3. Improve information and education.
hazards. 4. Limit access to high-alert medications.
5. Use labels and automated alerts.
SAFETY RISKS WITH MEDS ADMINISTRATION 6. Use redundancies (double checks).
a. Tablet splitting : done by patients to control cost. 7. Close monitoring of patient’s response.
b. Buying drugs over the internet.
o Issues: Convenience VS expired meds and Look-alike and Sound-alike Drug Names o Drugs involved
safety in medication errors and recognized as confusing
Recommendation: Look for sites that require includes:
prescription; Ask for a contact person & a licensed • Amaryl (glimepiride) VS Reminyl
pharmacist, should there be a need to call. (galantamine)
Counterfeit Drugs • Captopril VS carvedilol
Drugs that may look like the desired drug but • Depakote (valproic acid) VS Depakote ER
: o may have no active ingredient o wrong (divalproex Na)
amount of active ingredient o improper • Depo-medrol VS Solu-medrol
packaging o contaminated (methylprednisolones)
Recomm: Purchase drugs from licensed • ephedrine VS epinephrine
pharmacies. Report to the BFAD, DOH, PNP or
DTI. Recomm: Use of “tall-man” letters as a safety
strategy
Ex: rispiriDONE VS rOPINIRole : for listings &
storage
DOCUMENTATION o
MAR:
1. Name of the drug.
2. Dose
3. Route
4. Date and time
5. Refusal : reason for refusal
• FUMC: N/A if meds are
not available
THE NURSING PROCESS help to promote safe and effective use of the
Utilizing steps of nursing process ensures that the drug and prevent
interdisciplinary practice of pharmacology results in safe, adverse effects, clinically
effective, and individualized medication administration important drug–drug, drug–food,
and outcomes for patients. or drug– alternative therapy
Although not all nursing theorists completely agree on interactions, and medication
this process that defines the practice of nursing, most do errors.
include certain key elements: assessment, nursing
diagnosis, implementation, and evaluation. b. Chronic Conditions o Chronic conditions
Application of the nursing process with drug therapy can affect the
ensures that the patient receives the best, safest, most pharmacokinetics and
efficient, scientifically based, holistic care. pharmacodynamics of a drug.
Certain conditions (e.g., renal
disease, heart disease, diabetes,
chronic lung disease) may be
contraindications to the use of a
drug.
h. Pattern of Health Care o Knowing how a patient Five Types of Nursing Diagnosis
seeks health care provides the nurse with valuable
information to include when preparing the patient’s 1. Actual
teaching plan. Information about patterns of health o based on human responses and
care also provides insight into conditions that the supported by defining characteristics
patient may have but has not reported or 2. Risk/high-risk o patient may be more
medication use that has not been stated. susceptible to a particular problem
i. Physical Examination 3.
o To determine if any conditions exist Possib suspected problems requiring
that would be contraindications or le o additional data
cautions for using the drug and to 4.
develop a baseline for evaluating the Wellne clinical judgment about a transition
effectiveness of the drug and the ss o from one level to a higher level
occurrence of any adverse effects. 5. cluster signs and symptoms to
Syndro predict certain circumstances or
j. Weight me o events
o A patient’s weight helps to determine
PLANNING
whether the recommended drug dose
is appropriate. In the planning step, the nurse delineates specific
interventions directed at solving or preventing the
k. Age
problems identified in analysis. The plan must be
o The child’s developmental age will individualized for each patient. When creating a
influence pharmacokinetics and care plan, the nurse must define goals, set
pharmacodynamics; the immature liver priorities, identify nursing interventions, and
establish criteria for evaluating success. In addition
may not metabolize drugs in the same
to nursing interventions, the plan should include
way as in the adult, or the kidneys
interventions performed by other healthcare
may not be as efficient as those of an
providers. Planning is an ongoing process that
adult. As patients age, the body
must be modified as new data are gathered.
undergoes many normal changes that
can affect drug therapy, such as a
Four phases of a nursing care plan
decreased blood volume, decreased
a. Setting priorities o Identify
gastrointestinal absorption, reduced
problems and prioritize which ones
blood flow to muscles or skin, and
are more important and must be
changes in receptor-site attended to first, depending on
responsiveness. patient needs
b. Developing measurable goal/outcome
NURSING DIAGNOSIS statements o Write short- and long-term
The nurse analyzes the database to determine actual and goals for the patient to be followed
potential health problems. These problems may be when providing care
physiologic, psychologic, or sociologic. Each problem is c. Formulating nursing interventions and
stated in the form of a nursing diagnosis, which can be formulating anticipated therapeutic
defined as an actual or potential health problem that outcomes o Plan which
nurses are qualified and licensed to treat. intervention to use based on
anticipated patient behavior
A complete nursing diagnosis consists of two statements:
a) a statement of the patient's actual or potential health IMPLEMENTATION
problem, followed by
Involves taking the information gathered and
b) a statement of the problem's probable cause or risk
synthesized into nursing diagnoses to plan the
factors.
patient care. This process includes setting goals
and desired patient outcomes to assure safe and
Typically, the statements are separated by the phrase
effective drug therapy. These outcomes usually
related to, as in this example of a drug associated
involve ensuring effective response to drug therapy,
nursing diagnosis: “noncompliance with the prescribed
minimizing adverse effects, and understanding the
regimen [the problem] related to inability to
drug regimen.
selfadminister medication [the cause].”
Nursing actions are suggested o Dependent
actions: performed by a nurse based on health
care provider’s orders
o Interdependent actions: implemented with the
cooperation of a team
NCMA216: Pharmacology
LECTURE 4: THE NURSING PROCESS IN PHARMACOLOGY
MR. RENOVO ANGELES MIRADOR
1ST SEMESTER | A.Y. 2022-2023
o Independent actions: provided by nurse by virtue effects, and the occurrence of drug–drug, drug–
of education and license food, drug– alternative therapy, or drug–laboratory
test interactions. In some situations, the nurse
Three types of nursing interventions are frequently involved in evaluates the patient simply by reapplying the
drug therapy: beginning steps of the nursing process and then
a. drug administration analyzing for changes, either positive or negative.
b. provision of comfort measures The process of evaluation may lead to changes in
c. patient/family education. the nursing interventions being used to provide
better and safer patient care.
a. Proper Drug Administration o The nurse must
consider seven points, or “rights,” to ensure safe and
effective drug administration.
1. Right drug and patient,
2. Right storage of drug,
3. Right and most effective route,
4. Right dose,
5. Right preparation,
6. Right timing, and
7. Right recording of administration.
b. Comfort Measures
o A patient is more likely to be compliant with a drug
regimen if the effects of the regimen are not too
uncomfortable or overwhelming.
TERMINOLOGIES:
c. Placebo Effect o The anticipation that a drug will ASSESSMENT
be helpful (placebo effect) has proved to have o information gathering regarding the current
tremendous impact on the actual success of drug status of a particular patient, including
therapy. For example, a back rub, a kind word, and a evaluation of past history and physical
positive approach may be as beneficial as the drug examination; provides a baseline of information
itself. and clues to effectiveness of therapy.
EVALUATION
d. Managing Adverse Effects o Such interventions o part of the nursing process; determining the
include environmental control (e.g., temperature, light), effects of the interventions that were instituted
safety measures (e.g., avoiding driving, avoiding the for the patient and leading to further
sun, using side rails), and physical comfort measures assessment and intervention.
(e.g., skin care, laxatives, frequent meals). IMPLEMENTATION
o actions undertaken to meet a patient’s needs,
e. Lifestyle Adjustment o Some medications and their such as administration of drugs, comfort
effects require that a patient make changes in his or her measures, or patient teaching.
lifestyle. For example, patients taking diuretics may have NURSING
to rearrange their day so as to be near toilet facilities o the art of nurturing and administering to the
when the drug action peaks. Patients taking sick, combined with the scientific application of
bisphosphonates will need to plan their morning so they chemistry, anatomy, physiology, biology,
can take the drug on an empty stomach, stay upright for nutrition, psychology, and pharmacology to the
at least one-half hour, and plan their first food of the day particular clinical situation.
at least one-half hour after taking the drug. NURSING DIAGNOSIS
o statement of an actual or potential problem,
f. Patient and Family Education o With patients
based on the assessment of a particular clinical
becoming increasingly responsible for their own care, it situation, which directs needed nursing
is essential that they have all of the information interventions.
necessary to ensure safe and effective drug therapy at
NURSING PROCESS
home. In fact, many states now require that patients be
o the problem-solving process used to provide
given written information.
efficient nursing care; it involves gathering
EVALUATION
information, formulating a nursing diagnosis
Evaluation is part of the continuing process of patient care statement, carrying out interventions, and
that leads to changes in assessment, diagnosis, and evaluating the process.
intervention. The patient is continually evaluated for
therapeutic response, the occurrence of adverse drug
NCMA216: Pharmacology
LECTURE 5: DRUGS AFFEECTING THE BODY SYSTEM AND NURSING CONSIDERATIONS (ANS)
MR. RENOVO ANGELES MIRADOR
1ST SEMESTER | A.Y. 2022-2023
INTRODUCTION o The ganglia of the PNS are located near the organ
Drugs affecting the nervous system alter its functions. A of innervation. The neurons therefore of the PNS
thorough review of the anatomy and physiology of the are pre – ganglionic neuron, the neuron from the
Central Nervous System and Autonomic System would Cranio – sacral outflow to the ganglia and the post –
help students understand the mechanisms of actions of ganglionic neuron, the neuron from the ganglia to
drugs. The functional unit, neurons basic function is the organ of innervations. PNS is responsible for
impulse transmission which happen by electrical and “REST AND DIGEST” involuntary responses of the
chemical process. Electrical transmission of impulses body.
happen by action potential and chemical process make
use of neurotransmitters to achieve its functions. o Impulses transmitted across the synapses of the
ganglia are mediated also by the neurotransmitters.
CENTRAL NERVOUS SYSTEM
o Brain & Spinal Cord – very important structure of o In the PNS, the neurotransmitter is Acetylcholine.
the CNS is its protective mechanisms that not all Receptors for acetylcholine are located in the post
chemicals can pass through it, this affects the synaptic neuronal membrane. These receptors are
pharmacodynamics of drugs because some of them called cholinergic receptors. There are 2 types of
cannot penetrate the CNS. One vital protective cholinergic receptors
structure is the Blood Brain Barrier (BBB). This • Nicotinic Receptors
represents therapeutic challenge to drug treatment • Muscarinic receptors
of brain related disorders because a large
percentage of drugs are carried bound to plasma
proteins and are unable to cross the brain. SYMPATHETIC NERVOUS SYSTEM
o The division of the autonomic nervous system,
PERIPHERAL NERVOUS SYSTEM Sympathetic nervous system (SNS) from the
o Autonomic Nervous System & Somatic Nervous thoraco- lumbar outflow, spinal nerves from this
System – Synapses made by the peripheral region send nerve fibers to the sympathetic ganglia
nervous system conduct impulses that is chemical located near the CNS, then post ganglionic neurons
in nature. These neurotransmitters have specific send innervation to the involuntary muscles and
receptors in the neural membrane to facilitate glands and other effectors mostly associated with
conduction of nerve impulses. Drugs may act in the involuntary process in the body.
nervous system to either stimulate or block the
receptors to correct alterations in the nervous o The preganglionic neuron of the SNS is shorter than
functions. PNS and the post ganglionic neuron is longer than
PNS. SNS is responsible for “FIGHT OR FLIGHT”
o Neurons conduct impulses by Action Potential, the involuntary responses of the body. Impulses
rapid change in the membrane potential, this transmitted across the synapses also are mediated
happens by movement of sodium into the cells by the neurotransmitters. There are two
causing depolarization and potassium out of the neurotransmitters in the SNS. Acetylcholine and
cells to cause repolarization. This movement of ions Epinephrine and Norepinephrine ( Catecholamines )
facilitated by channels in the cell membranes will be
acted upon by drugs to correct changes in the o Acetylcholine is released by the preganglionic
nervous system causing disease process. neurons, while epinephrine and norepinephrine are
the neurotransmitters released by the post
AUTONOMIC NERVOUS SYSTEM ganglionic neurons, except for those post ganglionic
o The division of the peripheral nervous system that neurons innervating adrenal medulla, pilo erector
supply involuntary muscles, glands and other muscles, sweat glands and some smooth muscles
effectors not innervated by the somatic nervous of the blood vessels, they have sympathetic
system. Autonomic nervous system is responsible innervations but the neurotransmitter in at the
for all involuntary actions of the body that the postganglionic neurons is Acetylcholine
person is not aware of. This is divided into two
divisions: o Epinephrine and Norepinephrine may also be called
Adrenalin and Noradrenaline respectively or they
PARASYMPATHETIC NERVOUS SYSTEM are being referred to as catecholamines. Their
o Parasympathetic nervous system (PNS) comes receptors are called Adrenergic Receptors.
from the cranio – sacral outflow of the peripheral
nervous system. Cranial nerve X, IX, VII, III o There are 2 types of adrenergic receptors
participate in the cranial flow. Majority of the PNS • Alpha receptors
comes from cranial nerve X ( Vagus nerve ). This is • Beta receptors
the only cranial nerves that extend up to the thorax
and abdomen to supply majority of parasympathetic
innervation, so a vagal stimulation is synonymous
with parasympathetic innervation. Sacral nerves
also participate in the PNS to supply mostly the
effectors in the pelvic area like urinary bladder.
NCMA216: Pharmacology
LECTURE 5: DRUGS AFFEECTING THE BODY SYSTEM AND NURSING CONSIDERATIONS (ANS)
MR. RENOVO ANGELES MIRADOR
1ST SEMESTER | A.Y. 2022-2023
DRUG AFFECTING THE AUTONOMIC NERVOUS SYSTEM ARE • Adverse effects: These are related to
CALLED AUTONOMIC DRUGS increase parasympathetic responses such
Classifications of Autonomic Drugs as bradycardia, diarrhea, urinary
o Drugs affecting the PNS are called Cholinergic incontinence. Increase sweating may
Drugs happen because of the acetylcholine
present in the sweat glands.
o Drugs affecting the SNS are called Adrenergic
Drugs • Drug – Drug interaction: Effects of these
drugs maybe increase if combined with
anticholinesterase drugs or the indirect
In the study of pharmacodynamics, one action of the drugs is acting cholinergic agonists.
its binding with the receptors that may stimulate the • Examples
receptors (drugs are called agonist) and drugs that may ▪ Bethanecol – indicated for non –
block the receptors (drugs are called antagonists). If a obstructive urinary retention like
student is aware of the responses of the PNS and SNS, it in neurogenic bladder
would be easier to remember drug actions, they would either ▪ Carbachol – indicated for
stimulate the receptors and produce the same effect or block glaucoma, causing pupillary
the receptors or inhibit the effects. constriction
▪ Pilocarpine – indicated for
Most of the effectors are innervated by both sympathetic and glaucoma, causing pupillary
parasympathetic and in such case the response of the body constriction
is opposite. See examples below:
o Indirect acting cholinergic agonist – this
drug increases acetylcholine effect by inhibiting
the action of acetylcholinesterase (an enzyme
that removes acetylcholine in the synapse. If
acetylcholinesterase is not removed in the
synaptic cleft, more acetylcholine stays in the
synapse stimulating more receptors, thus
Therefore, if a drug stimulates the receptors for PNS, it is enhancing their effects. These drugs are used
called cholinergic agonist, enhancing PNS effect so such for treatment of Myasthenia gravis and
drug is also referred to as parasympathomimetic drug. A Alzheimer’s disease
drug that blocks the cholinergic receptors is called
cholinergic antagonist, also called anticholinergic drugs, Myasthenia gravis
inhibiting PNS response and such drug may also be referred o is an autoimmune disease of the
to as parasympatholytic drug neuromuscular junction (NMJ). This is
characterized by destruction of cholinergic
If a drug stimulates receptors for SNS, it is called adrenergic receptors at the NMJ that will slow down
agonist, increasing SNS effect so such drug is also referred impulses going to the skeletal muscles. This
to as sympathomimetic drugs. A drug that blocks the disease is characterized by the development of
adrenergic receptors decreases SNS responses called muscle weakness and paralysis. To increase
adrenergic agonist or it is also called sympatholytic junctional transmission, indirect acting
drugs. cholinergic agonist inhibits acetylcholinesterase
making more acetylcholine present in the
Remember, knowing the responses of the PNS and SNS is junction to improve impulse transmission and
very important to understand actions of autonomic drugs, muscle function. These drugs are also called
because these drugs would only stimulate or block the anticholinesterase drugs.
receptors.
For the sake of the discussion and the given examples of hypertension, gastrointestinal depression and
drugs, the effects of some of drugs in particular receptors will genitourinary effects like urinary retention
be discussed first. o Examples
• Alpha 1 adrenergic agonist –
Alpha 1 receptors when stimulated will cause Phenylephrine used for treatment of
vasoconstriction, pupillary dilation and closure of urinary common colds and allergy. This drug
bladder sphincter causing urinary retention. causes vasoconstriction to lessen
When the receptors are block? What would be the expected congestion in the nose therefore called
effects? decongestants.
• Alpha 2 adrenergic agonist – Clonidine
Alpha 2 receptors in the CNS neurons when stimulated will better known for its brand name as
decrease norepinephrine flow from the CNS to the SNS Catapres acting on the CNS neurons to
therefore decreasing sympathetic response. Take note that decrease norepinephrine flow. This drug is
this is the drug that stimulate adrenergic receptors but indicated for treatment of hypertension.
decreasing SNS effect because the receptors being
stimulated are located in the CNS. 3. Beta specific adrenergic agonist – these drugs
specifically stimulate the beta receptors and not the
Beta 1 receptors in the heart when stimulated will increase alpha receptors.
heart rate. When we use a drug that blocks the receptor,
what is the effect? o Pharmacokinetics: well absorbed and distributed in
the body, metabolized in the liver and excreted in
Beta 2 are located in the lungs, if we use a drug that the urine. The drugs pass the placenta and
stimulates receptors, the effect is bronchodilation, what is the breastmilk, use in pregnancy and lactation only if
effect if we block the receptor? benefits outweigh the risks
o Contraindications and Cautions: The drugs are
CLASSIFICATION OF ADRENERGIC AGONIST DRUGS contraindicated in clients with allergy to the drugs.
1. Alpha and Beta adrenergic drugs ( Caution is used in clients with cardiovascular
Sympathomimetic drugs ) – these drugs stimulate all disease like hypertension and tachycardia.
adrenergic receptors to enhance their effects. o Adverse effects: These are related to the primary
effects of drugs which will increase sympathetic
o Pharmacokinetics: these drugs are rapidly effects like hypertension and tachycardia.
absorbed, metabolized in the liver and excreted in o Examples
the urine. These drugs may cross the placenta and • Isoproterenol – for treatment of
breastmilk cardiogenic shock and heartblock in
o Contraindications and Cautions: Should not be transplanted heart.
given in client with allergy to these drugs and to • Salbutamol – for treatment of obstructive
patients with pheochromocytoma as the drugs may respiratory disease like COPD and
exacerbate the signs and symptoms bronchial asthma
o Adverse effects: These are all related to increase
SNS response like tachycardia, hypertension, Nursing Considerations
constipation, urinary retention, pupillary dilation 1. Avoid sudden withdrawal of the drug because it
o Examples may cause rebound hypertension, arrhythmias and
• Epinephrine – the drug of choice during flushing
CPR, indicated for treatment of shock 2. Monitor vital signs especially blood pressure and
• Dobutamine – used for treatment of heart rate o Avoid comfort measures including rest
congestive heart failure o Dopamine – and environmental control to decrease CNS
usually given for congestive heart failure irritation.
and cardiogenic shock 3. Provide adequate health teaching on the name of
• Norepinephrine – like epinephrine, may drug, prescribed dosage, effects and adverse
be indicated for cardiac arrest effects to increase patient’s knowledge and
subsequent compliance.
2. Alpha specific adrenergic agonist – these drugs
specifically stimulate only the alpha receptors and not CLASSIFICATION OF ADRENERGIC ANTAGONIST DRUGS
the beta receptors (SYMPHATOLYTIC DRUGS)
1. Alpha and Beta adrenergic antagonist – these drugs
o Pharmacokinetics: these drugs are well absorbed block all adrenergic receptors
and distributed, reach peak levels in 20 to 45
minutes. These drugs are metabolized in the liver o Pharmacokinetics: these drugs are well absorbed
and excreted in the urine and distributed in the body, metabolized in the liver
o Contraindications and Cautions: these drugs are not and excreted in the urine and the feces.
indicated to clients with allergy to the drugs, those o Contraindications and Cautions: These drugs
with hypertension and close angle glaucoma. should not be given to clients with allergy to the
o Caution is used in clients with cardiovascular drugs. To those with hypotension and bradycardia.
disease. Caution is used in clients with cardiovascular
o Adverse effects: these are related to the overdose disease and obstructive lung disorders
of drugs that may increase sympathetic effects like
NCMA216: Pharmacology
LECTURE 5: DRUGS AFFEECTING THE BODY SYSTEM AND NURSING CONSIDERATIONS (ANS)
MR. RENOVO ANGELES MIRADOR
1ST SEMESTER | A.Y. 2022-2023
o Adverse effects: these mainly on the effects of the are most commonly known as beta blockers. These
drugs in the lungs like bronchospasm, blood drugs are indicated to clients with hypertension,
vessels causing vasodilation and hypotension. dysrhythmias, angina and use to support cardiac
o Examples function in clients with congestive heart failure
• Carvedilol
• Labetalol o Pharmacokinetics: these drugs are absorbed in the
Both examples maybe indicated to gastrointestinal tract and undergo hepatic
clients with severe hypertension metabolism. The presence of food may increase the
caused by pheochromocytoma bioavailability of some beta blockers. These drugs
are known teratogenic in animals as it passes the
2. Alpha adrenergic antagonist – these drugs block only placenta and breast milk
the alpha receptors, specific drugs act on the alpha 1 o Contraindications and Cautions: Contraindicated in
and alpha 2 receptors. clients with allergy to the drugs. Caution should be
used in clients with bradycardia and heart block as
o Pharmacokinetics: these drugs are well absorbed well on patients with obstructive lung diseases like
and distributed, metabolized in the liver and COPD and bronchial asthma
excreted in the urine. o Adverse effects: these are related to the
o Contraindications and Cautions: The drugs should bradycardia and bronchoconstriction effect of the
not be given to clients with hypotension and urinary drug. Gastrointestinal effects like nausea and
incontinence vomiting, genitourinary symptoms may be disturbing
o Adverse effects: related to the primary action of the to clients as well.
drug causing vasodilation and hypotension o Examples
o Examples • Beta adrenergic antagonists or Beta
• Phentolamine – more specific drug blockers
hypertension in pheochromocytoma, that ▪ Propranolol
will have less adverse effects. ▪ Pindolol