PHARMACOLOGY
 Adverse effects: drug effects, sometimes
called side effects, that are not the desired
therapeutic effects; may be unpleasant or
even dangerous
 Brand name: name given to a drug by the
pharmaceutical company that developed it;
also called a trade name or proprietary name
 Chemical name: name that reflects the
chemical structure of a drug
 Drugs: chemicals that are introduced into
the body to bring about change
 Food and Drug Administration (FDA):
federal agency responsible for the regulation
and enforcement of drug evaluation and
distribution policies
 Generic drugs: drugs sold by their generic
name; not brand name or trade name product
generic name: the original designation that a
drug is given when the drug company that
developed it applies for the approval process
 Genetic engineering: process of altering
DNA, usually of bacteria, to produce a
chemical to be used as a drug
 Orphan drugs: drugs that have been
discovered but would not be profitable for a
drug company to develop; usually drugs that
would treat only a small number of people;
these orphans can be adopted by drug
companies to develop
 Over-the-counter (OTC) drugs: drugs that
are available without a prescription for selftreatment of a variety of complaints; deemed
to be safe when used as directed; often
formerly only available by prescription
 Pharmacology: the study of the biological
effects of chemicals
 Pharmacotherapeutics: clinical
pharmacology—the branch of pharmacology
that deals with drugs; chemicals that are
used in medicine for the treatment,
prevention, and diagnosis of disease in
humans
 Phase I study: a pilot study of a potential
drug using a small number of selected,
usually healthy human volunteers
 Phase II study: a clinical study of a
proposed drug by selected physicians using
actual patients who have the disorder the
drug is designed to treat; patients must
provide informed consent
 Phase III study: use of a proposed drug on
a wide scale in the clinical setting with
patients who have the disease the drug is
thought to treat
 Phase IV study: continuous evaluation of a
drug after it has been released for marketing
 Preclinical trials: initial trial of a chemical
thought to have therapeutic potential; uses
laboratory animals, not human subjects
 Teratogenic: having adverse effects on the
fetus
The nurse is in a unique position regarding drug
therapy because nursing responsibilities include the
following:
 Administering drugs
 Assessing drug effects
 Intervening to make the drug
regimen more tolerable
 Providing patient teaching about
drugs and drug regimens
 Monitoring the overall patient care
plan to prevent medication errors
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
Drugs also may be processed using a synthetic
version of the active chemical found in a plant. An
example of this type of drug is dronabinol
(Marinol), which contains the active ingredient
delta-9-tetrahydrocannabinol found in
marijuana. This drug helps to prevent nausea and
vomiting in cancer patients but does not have all the
adverse effects that occur when the marijuana leaf is
smoked. Marijuana leaf is a controlled substance
with high abuse potential and is legal for medical
use in some states but not approved for recreational
use in most states.
SOURCES
OF
DRUGS
 Plants,
 Animals, and
 Inorganic compounds.
Natural Sources: Chemicals that might prove
useful as drugs can come from many natural
sources, such as plants, animals, or inorganic
compounds. To become a drug, a chemical must
have a demonstrated therapeutic value or efficacy
without severe toxicity or damaging properties.
Plants: Plants and plant parts have been used as
medicines since prehistoric times. Even today,
plants are an important source of chemicals that are
developed into drugs. For example, digitalis used to
treat cardiac disorders and various opiates used for
sedation were originally derived from plants.
Animal Products: Animal products are used to
replace human chemicals that fail to be
produced because of disease or genetic problems.
Until recently, insulin for treating diabetes was
obtained exclusively from the pancreas of cows
and pigs. Now genetic engineering—the process of
altering DNA—permits scientists to produce human
insulin by altering Escherichia coli bacteria, making
insulin a better product without some of the
impurities that come with animal products.
Thyroid drugs and growth hormone preparations
also may be obtained from animal thyroid and
hypothalamic tissues. Many of these preparations
are now created synthetically, however, and the
synthetic preparations are considered to be purer
and safer than preparations derived from animals.
Inorganic Compounds
Salts of various chemical elements can have
therapeutic effects in the human body. Aluminum,
fluoride, iron, and even gold are used to treat
various conditions. The effects of these elements
usually were discovered accidentally when a cause–
effect relationship was observed
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
(NASA PAGE 6 NG PDF NA 'TOOOO KASORA)
FDA Pregnancy Categories
Category A
Adequate and well-controlled studies have failed to demonstrate a risk to the fetus in the first trimester of
pregnancy (and there is no evidence of risk in later trimesters). (SAFEST. WALA ADV EFFECTS)
Category B
Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and
well-controlled studies in pregnant women. (WALA SA FETUS PERO WALA PA STUDIES ABOUT SA
PREG WOMEN)
Category C
Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and
well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women
despite potential risks. (MAY ADV EFFECT SA FETUS PERO PWEDENG MAY BENEFITS PA RIN SA
PREG WOMAN)
Category D
There is positive evidence of human fetal risk based on adverse reaction data from investigational or
marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant
women despite potential risks. (MAY RISK BASED ON INV/MARKETING EXPERIENCE IN HUMANS) KIMI
EWAN KO BA MEDJ HINDI KO GETS TO BASTA MAY BASED BASED KEMERUT
Category X
Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of
human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks
involved in use of the drug in pregnant women clearly outweigh potential benefits. (absolutely contraindicated
in pregnancy. NOT SAFE)
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
SYNTHETIC: Made by chemical synthesis
When the nucleus of the drug from
Synthetic drug: A 
drug that is
natural source as well as its chemical
prepared using
structure altered.
certain chemicals
instead of natural
 Aim to mimic the effect of existing
species with a
specific procedure
drug
drugs must pass through several stages of development.
These include preclinical trials and phase I, II, and III
studies
 PRECLINICAL TRIALS:
In preclinical trials, chemicals that may have
therapeutic value are tested on laboratory animals for two
by a human
main purposes:
SEMI SYNTHETHIC: When the nucleus of the
 To determine whether they have the presumed
drug obtained from natural source is retained but the
chemical structure is altered
effects in a living tissue
Ex. Ampicillin, Morphine, Ethinyl Estradiol
 To evaluate any adverse effects
 Microbiological Sources
Fungi –Penicillium Notatum which gives Penicillin Reasons for discarding some chemicals:
 Chemicals lack therapeutic activity when used
Gentamicin and Tobramycin are derived from
Streptomycis and micromonosporas
with living animals
medicines are
Actinobacteria give Streptomycin semi-synthetic
derived from naturally
 Chemical is too toxic to living animals to be
occurring substances
worth the risk of developing into a drug
extracted from sources such
Key Points
as plants, bacteria or animal
 Chemical is highly teratogenic (causing adverse
cells.
effects to the fetus)
o Clinical pharmacology is the
study of drugs used to treat,
 The safety margins are so small that the chemical
diagnose, or prevent a disease.
would not be useful in the clinical setting
o Drugs are chemicals that are
introduced into the body and affect the
 PHASE I STUDIES
body’s chemical processes.
Uses human volunteers to test the drugs.
o Drugs can come from natural
More tightly controlled than preclinical trials and are
sources including plants, foods,
performed by specially trained clinical investigators
animals, salts of inorganic
compounds, or synthetic sources.
 PHASE II STUDIES
Drug Evaluation
Allows clinical investigators to try out the drug in
patients who have the disease that the drug is designed to
After a chemical that might have therapeutic
value is identified, it must undergo a series of treat.
scientific tests to evaluate its actual
therapeutic and toxic effects. This process is
 PHASE III STUDIES
tightly controlled by the U.S. Food and Drug Involves use of the drug in a vast clinical market.
Administration (FDA), an agency of the U.S. Prescribers are informed of all the known reactions to the
Department of Health and Human Services
drug and precautions required for its safe use.
that regulates the development and sale of
Food and drug administration (FDA) approval
drugs. FDA regulated tests are designed to
Drugs that finish phase iii studies are evaluated by the FDA,
ensure the safety and reliability of any drug
which relies on committees of experts familiar with the
approved in this country. For every 100,000
specialty area in which the drugs will be used.
chemicals that are identified as being potential Only those drugs that receive FDA committee
drugs, only about five end up being marketed. approval may be marketed.
Before receiving final FDA approval to be
marketed to the public,
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
 PHASE IV STUDIES
After a drug is approved for marketing, it enters a phase
of continual evaluation, or phase iv study.
Prescribers are obligated to report to the FDA any
untoward or unexpected adverse effects associated with
drugs they are using, and the fda continually evaluates
this information.
LEGAL REGULATION OF DRUGS
S
O
C
O
G
o
o
o
o
o
SAFETY DURING PREGNANCY
CONTROLLED SUBSTANCES
GENERIC DRUGS
ORPHAN DRUGS
OVER THE COUNTER DRUGS
FOOD AND DRUG ADMINISTRATION PREGNANCY
CATEGORIES
 CATEGORY A: ADEQUATE STUDIES IN
SOURCES OF DRUG INFORMATION:
o DRUG LABELS
o PACKAGE INSERTS
o REFERENCE BOOKS
o JOURNALS
o INTERNET INFORMATION
D
R
J
I
P
PHARMACODYNAMICS
THE STUDY OF THE INTERACTIONS BETWEEN THE
CHEMICAL COMPONENTS OF LIVING SYSTEM AND THE
FOREIGN CHEMICALS , INCLUDING DRUGS THAT ENTER
THOSE SYSTEMS
FOUR WAYS DRUGS WORK :
 REPLACE OR ACT AS SUBSTITUTE FOR
I
MISSING CHEMICALS
 INCREASE OR STIMULATE CERTAIN
D
CELLULAR ACTIVITIES
I
 DEPRESS OR SLOW CELLULAR ACTIVITIES
A
 TO INTERFERE WITH THE FUNCTIONING OF
FOREIGN CELLS
PHARMACOKINETICS
THE STUDY OF ABSORPTION, DISTRIBUTION ,
METABOLISM , AND EXCRETION OF DRUGS
PREGNANT WOMEN HAVE NOT DEMONSTRATED A
RISK TO THE FETUS IN THE FIRST TRIMESTER OF
PREGNANCY , AND THERE IS NO EVIDENCE OF RISK
IN LATER TRIMESTERS .
 CATEGORY B: ANIMAL STUDIES HAVE NOT PHARMACODYNAMICS
DEMONSTRATED A RISK TO THE FETUS, BUT THERE
 RECEPTOR SITES -Agonist & Antagonist
ARE NO ADEQUATE STUDIES IN PREGNANT WOMEN,
 DRUG ENZYME INTERACTIONS - If a single step in one of the
many enzyme systems is
OR ANIMAL STUDIES HAVE SHOWN AN ADVERSE
 SELECTIVE TOXICITY
blocked, normal cell function
The ability of a drug to attack only those systems found
EFFECT, BUT ADEQUATE STUDIES IN PREGNANT
is disrupted.
in foreign cells
WOMEN HAVE NOT DEMONSTRATED A RISK TO THE
PHARMACOKINETICS:
FETUS DURING THE FIRST TRIMESTER OF
PREGNANCY , AND THERE IS NO EVIDENCE OF RISK
CRITICAL CONCENTRATION – AMOUNT OF A DRUG
IN LATER TRIMESTERS .
THAT IS NEEDED TO CAUSE A THERAPEUTIC EFFECT
 CATEGORY C: ANIMAL STUDIES HAVE
SHOWN AN ADVERSE EFFECT ON THE FETUS, BUT
LOADING DOSE – IF EFFECTS ARE NEEDED QUICKLY
THERE ARE NO ADEQUATE STUDIES IN HUMANS;
HIGHER DOSE IS NEEDED FOR TREATMENT QUICKLY .
THE BENEFITS FROM THE USE OF THE DRUG IN
PREGNANT WOMEN MAY BE ACCEPTABLE DESPITE
 VERY LOW ANG SUGAR LVL. IV 50/50 GLUCOSE
ITS POTENTIAL RISKS, OR THERE ARE NO ANIMAL
(CC) PARA MA REVIVE AGAD SUGAR LVL.
REPRODUCTION STUDIES AND NO ADEQUATE
 ASTHMA ATTACK NAG KAKA DYSPNEA = LOADING
STUDIES IN HUMANS.
DOSE OF BRONCHODILATORS
 CATEGORY D: THERE IS EVIDENCE OF
HUMAN FETAL RISK, BUT THE POTENTIAL BENEFITS DYNAMIC EQUILIBRIUM – ACTUAL CONCENTRATION
FROM THE USE OF THE DRUG IN PREGNANT WOMEN THAT A DRUG REACHES IN THE BODY . IT IS INFLUENCE
MAY BE ACCEPTABLE DESPITE ITS POTENTIAL
BY THIS 4 PROCESSES
B
RISKS.
 ABSORPTION
E
 CATEGORY X: STUDIES IN ANIMALS OR
 DISTRIBUTION
D
HUMANS DEMONSTRATE FETAL ABNORMALITIES OR
 BIOTRANSFORMATION
ADVERSE REACTIONS ; REPORTS INDICATE
 EXCRETION
A
EVIDENCE OF FETAL RISK. THE RISK OF USE IN A
ABSORPTION it is influence by the:
PREGNANT WOMAN CLEARLY OUTWEIGHS ANY
Route of Administration
POSSIBLE BENEFIT
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
 Oral- Factors na nakaka influence sa
 Blood-Brain Barrier- The blood–brain barrier
kanilang absorption example: tablet form,
is a protective system of cellular activity that keeps many
capsule or in a solution. Iba iba rin ang rate
things (e.g., foreign invaders, poisons) away from the
of absorption, or sa gastric emptying kasi
CNS. Drugs that are highly lipid-soluble are more likely
may mga meds na need ng intake or with
to pass through the blood–brain barrier and reach the
meals & should be taken w/out meals
CNS
 Placenta and Breast milk- Many drugs readily
 Intravenous
 Intramuscular: Can be affected by the fat pass through the placenta and affect the developing fetus
in pregnant women.it is best not to administer any drugs
content of the muscle.
to pregnant women because of the possible risk to the
Same with the perfusion of the blood flow to the
fetus. Drugs should be given only when the benefit
muscle.
Temp of the muscle can also affect absorption of the clearly outweighs any risk.
medicine. If cold muscle ma decrease ang
Biotransformation (Metabolism)
absorption, pag may cold na iaabsorb sa body nag
Biotransformation occur in the Liver
cconstrict an gating mga muscle and tissues. If heat
 First Pass Effect- Breakdown of the drugs in
naman or warm na vasodilate an gating mga
the liver after absorption. Drugs that are taken orally are
cells/tissue kaya na increase ang absorption
usually absorbed from the small intestine directly into the
 Subcutaneous
portal venous system (the blood vessels that flow through
the liver on their way back to the heart). The enzyme
 Topical
system immediately works on the absorbed drug to bio
 Inhalation
transform, then pag asa liver na Hepatic Enzyme System
Absorption Processes
na
 Passive Diffusion- Happens during
 Hepatic Enzyme System- The intracellular
absorption, major process to which drugs are
structures
of the hepatic cells are lined with enzymes
absorbed in the body. It does not require any
packed
together
cellular energy for the drug to be absorbed,
it passes from greater concentration to lower
Excretion- Removal of a drug from the body.
concentration so by pull of gravity na pass
The skin, saliva, lungs, bile, and feces are some of the
ng chemicals into the body
routes used to excrete drugs.
 Active Transport- It requires energy to
The kidneys, however, play the most important role in
actively move a molecule across the cell
drug excretion
membrane. It is not much involved in
Drugs that have been made water-soluble in the liver are
absorption, it is more on drug excretion.
often readily excreted from the kidney by glomerular
 Filtration- Movement propose in the cell
filtration—the passage of water and water-soluble
membrane. Facilitated or push by osmotic
components from the plasma into the renal tubule.
pressure. Hydrostatic or by blood
Distribution (3 ways on drug being distributed in Half-Life- The time it takes for the amount of drug in
the body to decrease to one half of the peak level it
the body)
previously achieved. This will depend on how the body
 Protein bindingprocesses and gets rids of the drug, can be few
Na bind siya sa protein in our body. Some of the
hours/days/week.
chemicals are large enough that cannot enter the
Ex: Cetirizine or Anti-Histamine: Can only be taken up
capillaries for the tissue to react.
Most drugs are bound to some extent to proteins in to 3 days most or least. The usual dosage is once at
bedtime for 3 days.
the blood to be carried into circulation. The more
Potency na reduce into half of its potency, and may mga
bound to the protein, the more difficult it can be
times na ini-extend that’s why follow up checkup is
for the medication to be released and able to cross
membranes to get to the tissue cells. The drug must important.
be freed from the protein’s binding site to act on the
tissues.
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
 Environmental Factors- Some drug effects
 Weight- People who are much heavier may are enhanced by a quiet, cool, nonstimulating
require larger doses to get a therapeutic effect from environment.
 Tolerance- The body may develop a tolerance to
a drug because they have increased tissues to
perfuse and increased receptor sites in some reactive some drugs over time. Tolerance may arise because of
increased biotransformation of the drug, increased
tissue. People who weigh less than the norm may
resistance to its effects, or other pharmacokinetic factors.
require smaller doses of a drug.
 Cumulation- If a drug is taken in successive
 Age- Children metabolize many drugs
doses at intervals that are shorter than recommended, or
differently than adults do, and they have immature
if the body is unable to eliminate a drug properly, the
systems for handling drugs.
drug can accumulate in the body, leading to toxic levels
 Gender- When giving IM injections, for
example, it is important to remember that men have and adverse effects.
 Interactions- When two or more drugs or
more vascular muscles, so the effects of the drug
substances are taken together, there is a possibility that an
will be seen sooner in men than in women.
interaction can occur, causing unanticipated effects in the
Women have more fat cells than men do, so drugs
that deposit in fat may be slowly released and cause body
-------------------------------------------------------------------effects for a prolonged period.
TOXIC EFFECTS OF DRUGS
 Physiological Factors- diurnal rhythm of
ADVERSE EFFECTS : UNDESIRED EFFECTS THAT
the nervous and endocrine systems, acid–base
MAY BE UNPLEASANT OR EVEN DANGEROUS
balance, hydration, and electrolyte balance can
affect the way that a drug works on the body and the Types:
 Primary Actions- One of the most common
way that the body handles the drug.
occurrences
in drug therapy is the development of
 Pathological Factors- GI disorders can
adverse effects from simple overdose. In such cases, the
affect the absorption of many oral drugs.Vascular
patient suffers from effects that are merely an extension
diseases and low blood pressure alter the
of the desired effect
distribution of a drug, preventing it from being
For example, an anticoagulant may act so effectively that
delivered to the reactive tissue, thus rendering the
drug nontherapeutic. Liver or kidney diseases affect the patient experiences excessive and spontaneous
bleeding. This type of adverse effect can be avoided by
the way that a drug is biotransformed and excreted
monitoring the patient carefully and adjusting the
and can lead to toxic reactions when the usual
prescribed dose to fit that particular patient’s needs
dose is given.
 Secondary Actions - Patient needs to be informed
 Genetic Factors- Some people lack certain
enzyme systems necessary for metabolizing a drug, that these effects may occur and counseled about ways to
whereas others have overactive enzyme systems that cope with the undesired effects.
For example, many antihistamines are very effective in
cause drugs to be broken down more quickly. Still
drying up secretions and helping breathing, but they also
others have differing metabolisms or slightly
cause drowsiness. The patient who is taking
different enzymatic makeups that alter their
antihistamines needs to know that driving a car or
chemical reactions and the effects of a given drug.
operating power tools or machinery should be avoided
Pharmacogenomics is a new area of study that
explores the unique differences in response to drugs because the drowsiness could be dangerous.
 Hypersensitivity- It may result from a pathological
that each individual possesses based on genetic
or underlying condition.
makeup.
For example, many drugs are excreted through the
 Immunological Factors- People can
kidneys; a patient who has kidney problems may not be
develop an allergy to a drug. After exposure to its
proteins, a person can develop antibodies to a drug. able to excrete the drug and may accumulate the drug in
the body, causing toxic effects.
 Psychological Factors- The patient’s
-----------------------------------------------------------------------attitude about a drug has been shown to have an
Drug allergy: Occurs when the body forms antibodies to a
effect on how that drug works. A drug is more
particular drug, causing an immune response when the person
likely to be effective if the patient thinks it will
is re-exposed to the drug
work than if the patient believes it will not work.
This is called the placebo effect
Factors influencing Drug Effects:
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
Drug-induced tissue and organ damage: Drugs can act Intervention:
directly or indirectly to cause many types of adverse
Restore glucose—orally, if possible, or intravenously.
effects in various tissues, structures and organs
Provide supportive measures (e.g., skin care,
Toxicity
These effects are not acceptable adverse effects but
are potentially serious reactions to a drug
 Liver Injury- Oral drugs are absorbed and
passed directly into the liver in the first-pass effect.
This exposes liver cells to the full impact of the
drug before it is broken down for circulation
throughout the body. Most drugs are metabolized
in the liver, so any metabolites that are irritating or
toxic will also affect liver integrity
Interventions:
Discontinue the drug and notify the prescriber
and/or primary caregiver.
Offer supportive measures such as small, frequent
meals; skin care; a cool environment; and rest
periods
 Renal Injury- The glomerulus in the kidney
has a very small capillary network that filters the
blood into the renal tubule. Some drug molecules
are just the right size to get plugged into the
capillary network, causing acute inflammation and
severe renal problems. Some drugs are excreted
from the kidney unchanged; they have the potential
to directly irritate the renal tubule and alter normal
absorption and secretion processes. Gentamicin
(generic), a potent antibiotic, is frequently
associated with renal toxicity.
Interventions:
Notify the prescriber and/or primary caregiver and
discontinue the drug as needed.
Offer supportive measures—for example,
positioning, diet and fluid restrictions, skin care,
electrolyte therapy, rest periods, and a controlled
environment. In severe cases, be aware that dialysis
may be required for survival.
 Poisoning- Occurs when an overdose of a
drug damages multiple body systems, leading to the
potential for fatal reactions.
environmental control of light and temperature,
rest). Institute safety measures to prevent injury or falls.
Monitor blood glucose levels to help stabilize the
situation. Offer reassurance to help the patient cope with
the experience.
 Hyperglycemia- Some drugs stimulate the
breakdown of glycogen or alter metabolism in such
a way as to cause high serum glucose levels, or
hyperglycemia. Ephedrine (generic), a drug used as a
bronchodilator and antiasthma drug and to relieve
nasal congestion, can break down stored glycogen and
cause an elevation of blood glucose by its effects on the
sympathetic nervous system.
Intervention:
Administer insulin therapy to decrease blood glucose as
appropriate, while carefully monitoring glucose levels.
Provide support to help the patient deal with signs and
symptoms (e.g., provide access to bathroom facilities,
control the temperature of the room, decrease stimulation
while the patient is in crisis, offer reassurance, provide
mouth care—the patient will experience dry mouth and
bad breath with the ensuing acidosis, and mouth care will
help to make this more tolerable)
Electrolyte imbalances
 Hypokalemia- Some drugs affecting the kidney
can cause low serum potassium levels (hypokalemia) by
altering the renal exchange system.
Interventions
Replace serum potassium and carefully monitor serum
levels and patient response; achieving the desired level
can take time, and the patient may experience high
potassium levels in the process. Provide supportive
therapy (e.g., safety precautions to prevent injury or falls,
reorientation of the patient, comfort measures for pain
and discomfort). Cardiac monitoring may be needed to
evaluate the effect of the fluctuating potassium levels on
heart rhythm.
 Hyperkalemia- Some drugs that affect the
kidney, such as the potassium-sparing diuretics, can lead
Alterations in glucose metabolism
to potassium retention and a resultant increase in serum
 Hypoglycemia- Some drugs affect
potassium levels (hyperkalemia).
metabolism and the use of glucose, causing a low
Interventions
serum blood glucose concentration, or
Institute measures to decrease the serum potassium
hypoglycemia. Glipizide (Glucotrol) and glyburide concentration, including use of sodium polystyrene
(DiaBeta) are antidiabetic agents that have the
sulfonate (Kayexalate). When trying to stabilize
desired action of lowering the blood glucose level
the potassium level, it is possible that the patient may
but can lower blood glucose too far, causing
experience low potassium levels. Careful monitoring is
hypoglycemia
important until the patient’s potassium levels are stable.
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
Offer supportive measures to cope with
the patient to avoid dangerous situations such as driving a
discomfort. Institute safety measures to prevent
car or operating dangerous machinery.Orient the patient
injury or falls. Monitor for cardiac irregularities
and provide support. Consult with the prescriber to
because potassium is an important electrolyte in the decrease drug dose or discontinue the drug.
action potential, which is needed for cell membrane
 Atropine-like (anticholinergic) effects- Some
stability. When potassium levels are too high, the
drugs block the effects of the parasympathetic nervous
cells of the heart become very irritable and
system by directly or indirectly blocking cholinergic
rhythm disturbances can occur. Be prepared for a
receptors. Atropine, a drug used preoperatively to dry up
possible cardiac emergency. In severe cases, be
secretions and any other indications, is the prototype
aware that dialysis may be needed
anticholinergic drug. Many cold remedies and
antihistamines also cause anticholinergic effects
Sensory effects
 Ocular damage- The blood vessels in the
Interventions
retina are very tiny and are called “end arteries,”
Provide sugarless lozenges and mouth care to help mouth
that is, they stop and do not interconnect with other dryness. Arrange for bowel program as appropriate.
arteries feeding the same cells. Some drugs are
Provide safety measures if vision changes
deposited into these tiny arteries, causing
occur. Arrange for medication for headache and nasal
inflammation and tissue damage. Chloroquine
congestion as appropriate. Advise the patient to avoid hot
(Aralen), a drug used to treat some rheumatoid
environments and to take protective measures to prevent
diseases, can cause retinal damage and even
falling and to prevent dehydration, which may be caused
blindness.
by exposure to heat owing to decreased sweating
Interventions
 Parkinson-like syndrome- Drugs that directly or
Monitor the patient’s vision carefully when the
indirectly affect dopamine levels in the brain can cause a
patient is receiving known oculotoxic drugs.
syndrome that resembles Parkinson disease. Many of the
Consult with the prescriber and/or primary caregiver antipsychotic and neuroleptic drugs can cause this effect.
and discontinue the drug as appropriate. Provide
In most cases, the effects go away when the drug is
supportive measures, especially if vision loss is not withdrawn.
reversible. Monitor lighting and exposure to
Interventions
sunlight.
Discontinue the drug, if necessary. Know that treatment
 Auditory damage- Tiny vessels and nerves with anticholinergics or antiparkinson drugs may be
in the eighth cranial nerve are easily irritated and
recommended if the benefit of the drug outweighs the
damaged by certain drugs. The macrolide
discomfort of its adverse effects. Provide small, frequent
antibiotics, streptomycin in particular, can cause
meals if swallowing becomes difficult. Provide safety
severe auditory nerve damage. Aspirin, one of the
measures if ambulation becomes a problem.
most commonly used drugs, is often linked to
 Neuroleptic malignant syndrome- General
auditory ringing and eighth cranial nerve effects.
anesthetics and other drugs that have direct CNS effects
Interventions
can cause neuroleptic malignant syndrome (NMS), a
Monitor the patient’s perceptual losses or changes.
generalized syndrome that includes high fever; if not
Provide protective measures to prevent falling or
treated quickly, NMS can be fatal.
injury. Consult with the prescriber to decrease
Interventions
dose or discontinue the drug. Provide supportive
Discontinue the drug, if necessary. Know that treatment
measures to cope with drug effects
with anticholinergics or antiparkinson drugs may be
Neurological effects:
required. Provide supportive care to lower the body
 General CNS Effects- Although the brain is temperature. Institute safety precautions as needed.
fairly well protected from many drug effects by the
blood–brain barrier, some drugs do affect
Teratogenicity
neurological functioning, either directly or by
Ability of a drug to cause fetal abnormalities or
altering electrolyte or glucose levels. Beta-blockers, deformities
which are used to treat hypertension, angina, and
many other conditions, can cause feelings of
anxiety, insomnia, and nightmares.
Interventions
Provide safety measures to prevent injury. Caution
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
THE NURSING PROCESS & DRUG THERAPY
NURSING PROCESS:
o ASSESSMENT
The first step of the nursing process. This involves
systematic, organized collection of data about the
patient. Because the nurse is responsible for holistic care,
data must include information about physical,
intellectual,
emotional,
social,
cultural,
andenvironmental factors.
HISTORYHis or her past experiences and illnesses can influence a
drug’s effect. Knowledge of this important information
before beginning drug therapy will help to promote safe
and effective use of the drug and prevent adverse effects,
clinically important drug–drug, drug–food, or drug–
alternative therapy interactions, and medication errors.
Chronic Conditions
Drug use
Allergies
Level of Education and Understanding
Social and Financial Supports
Pattern of Health care
PHYSICAL EXAMINATIONIt is important to assess the patient’s physical status
before beginning drug therapy to determine if any
conditions exist that would be contraindications or
cautions for using the drug and to develop a baseline for
evaluating the effectiveness of the drug and the
occurrence of any adverse effects
Weight
Age
Physical parameters related to disease or drug effects
o NURSING DIAGNOSISSimply a statement of the patient’s status from a nursing
perspective. The nurse analyzes the information gathered
during assessment to arrive at some conclusions that lead
to a particular goal and set of interventions.
o PLANNINGInvolves taking and prioritizing the information gathered
and synthesized in the nursing diagnoses to plan the
patient care. This process includes setting goals and
desired patient outcomes to assure safe and effective
drug therapy.
o IMPLEMENTATIONInvolves nursing interventions aimed at achieving the
goals of outcomes determined in the planning phase.
Three types of nursing interventions are frequently
involved in drug therapy: drug administration, provision
of comfort measures, and patient/family education
PROPER DRUG ADMINISTRATION - The nurse
must consider eight points, or “rights,” to ensure
safe and effective drug administration. These are
right drug and patient, right storage of drug, right
and most effective route, right dose, right
preparation, right timing, and right recording of
administration
position to help the patient cope with the effects of drug
therapy. A patient is more likely to be compliant with a drug
regimen if the effects of the regimen are not too uncomfortable
or overwhelming
PATIENT AND FAMILY EDUCATION- With
patients becoming increasingly responsible for their own care,
it is essential that they have all of the information necessary to
ensure safe and effective drug therapy at home.
o EVALUATION
Part of the continuing process of patient care that leads to
changes in assessment, diagnosis, planning, and intervention.
The patient is continually evaluated for therapeutic response,
the occurrence of adverse drug effects, and the occurrence of
drug–drug, drug–food, drug–alternative therapy, or drug–
laboratory test interactions.
MEDICATION ERRORS
Reporting- These reports might prompt the issuing of
healthcare provider warnings, which point out potential or
actual medication errors and suggest ways to avoid these
errors in the future.
Nurse’s Role:
P, D, S, R, D, P, T, R
1. Right patient. It is always important to make sure that
you are giving the drug to the correct patient. Checking
the patient’s wrist band and asking the patient to repeat
his or her name and often birth date are
good policies to make sure it is the patient you think it is.
Avoid the error of asking a patient, “Are you Mr. Jones?”
The patient could respond yes without thinking or may
not have heard you correctly.
Rely on the patient telling you his or her name and read it
from the identification band. It is also important to make
sure this patient does not have allergies to the drug being
given and that the patient is not taking interacting drugs,
food, or alternative therapies.
2. Right drug. To prevent medication errors, always
check to make sure the drug you are going to administer
is the one that was prescribed. Many drugs may look
alike and or have sound-alike names. Ask for the
generic as well as the brand name if you are unsure.
Never assume the computer is correct; always doublecheck. Avoid abbreviations, and if you are not sure about
abbreviations that were used, ask. Make sure the
drug makes sense for the patient for whom it is ordered.
3. Right storage. Be aware that some drugs require
specific storage environments (e.g., refrigeration,
protection from light). Check to make sure that general
guidelines have been followed.
4. Right route. Determine the best route of
administration; this is frequently established by the
ROLLE, NICOLE ADRIENNE
COMFORT MEASURES- Nurses are in a unique
PHARMACOLOGY
formulation of the drug. Nurses can often have an
impact in modifying the route to arrive at the most
efficient, comfortable method for the patient based
on the patient’s specific situation. For example,
perhaps a patient is having trouble swallowing, and
a large capsule would be very difficult for the
patient to handle. The nurse could check and see if
the drug is available in a liquid form
and bring this information to the attention of the
person prescribing the drug. When establishing the
prescribed route, check the proper method of
administering a drug by that route. Review drug
administration methods periodically to make sure
you have not forgotten important techniques. If you
have instructed a patient in the proper
administration
of a drug, be sure to have the patient explain it back
to you and demonstrate the proper technique. This
should be done not only when the patient first learns
this technique but also periodically to make sure
he or she has not forgotten any important points.
Throughout this book, “Focus on Safe Medication
Administration” boxes will provide review of
proper medication administration technique.
5. Right dose. Always double-check calculations,
and always do the calculations if the drug is not
available in the dose ordered. Calculate
the drug dose appropriately, based on the available
drug form, the patient’s body weight or surface area,
or the patient’s kidney function. Do not assume that
the computer or the pharmacy is always right; you
are one more check in the system. Do not cut tablets
to get to a correct dose without checking to make
sure the tablet can be cut, crushed, or chewed. Many
tablets cannot be altered this way. Be very cautious
if you see an order that starts with a decimal point;
these orders are often the cause of medication
errors. You should never see .5 mg as an order
because it could be interpreted as 5 mg, 10 times the
ordered dose. The proper dose would be 0.5 mg. If
you see an order for 5.0 mg, be cautious; it could be
interpreted as 50 mg. If a dose seems too big,
question it. Throughout this book, “Focus on
Calculations” boxes will provide review for
calculating dose properly.
topical drugs may require specific handling, such as the
use of gloves during administration or shaving of a body
area before application. Many current oral drugs cannot
be cut, crushed, or chewed. Checking that information
can help to prevent serious adverse effects. If a drug
needs to be diluted or reconstituted, check the
manufacturer’s instructions to make sure that this is done
correctly.
7. Right time. When drugs are studied and evaluated, a
suggested timing of administration is established. This
timing takes into account all
aspects of pharmacokinetics to determine a dosing
schedule that will provide the needed therapeutic level of
the drug. Recognize that the administration of one drug
may require coordination with the
administration of other drugs, foods, or physical
parameters. In a busy hospital setting, getting the drug to
the patient at the prescribed time can be a real challenge.
As the caregiver most frequently involved in
administering drugs, the nurse must be aware of and
manage all of these factors, as well as educate the patient
to do this on his or her own. Organizing the day and the
drug regimen to make it the least intrusive on a patient’s
lifestyle can help to prevent errors and improve
compliance. Providing written instructions regarding
timing can be crucial in some situations.
8. Right recording. Always document drug
administration. If it isn’t written, it didn’t happen.
Document the information in accordance with
the local requirements for recording medication
administration after assessing the patient, making the
appropriate nursing diagnoses, and
delivering the correct drug, by the correct route, in the
correct dose, and at the correct time. Accurately record
the drug given and the time given only once you have
given the drug to avoid inadvertent overdoses or missing
doses, which would lead to a lack of therapeutic
effect. Encourage patients to keep track of their drugs at
home, what they take, and when they take it, especially if
they could be confused.
 Apothecary system: a very old system of
measure that was specifically developed for use by
apothecaries or pharmacists; it uses the minim as the
basic unit of liquid measure and the grain as the basic
6. Right preparation. Know the specific
unit of solid measure
preparation required before administering any drug.
 Clark rule: a method of determining the correct
For example, oral drugs may need to be crushed or drug dose for a child based on the known adult dose
shaken; parenteral drugs may need to be
(assumes that the adult dose is based on a 150-lb person);
reconstituted or diluted with specific solutions; and it states conversion: finding the equivalent values
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
between two systems of measure
 Fried rule: a method of determining a
pediatric drug dose for a child younger than 2 years
of age, based on the child’s age and the usual
adult dose (assumes that an adult dose would be
appropriate for a 12.5- year-old child); it states
 Metric system: the most widely used
system of measure, based on the decimal system; all
units in the system are determined as multiples of
10 ratio and proportion: an equation in which a ratio
containing two known equivalent amounts is on one
side and a ratio containing the amount desired to
convert and its unknown equivalent is on the other
side
 Young rule: a method for determining
pediatric drug dose based on the child’s age and the
usual adult dose; it states
those of the apothecary and household systems. The
avoirdupois system is seldom used by prescribers but
may be used for bulk medications that come directly
from the manufacturer
o Ounces
o Grains
Other Systems
o Unit
o Milliequivalent

o
o
o

o
o
o
o


Conversion between Systems:
Metric
Apothecary
Household
Calculating Dose
Oral
Parenteral
Intravenous Solutions
Pediatric Considerations
Parenteral Drugs
Pediatric Considerations
ORAL DRUGS
The ratio containing the two known equivalent
amounts is put on one side of the equation, and the ratio
containing the unknown value is put on the other side.
The known equivalent is the amount of drug available in
one tablet or capsule; the unknown is the number of
tablets or capsules that are needed for the prescribed
dose:
Dosage Calculations
 Measuring Systems
Metric System: most widely used system of
measure. It is based on the decimal system, so all
Example: An order is written for 10 grains of aspirin (gr
units are determined as multiples of 10.
x, aspirin). The tablets that are available each contain 5
o Gram - solid measure
grains. How many tablets should the nurse give? First, set
o Liter - liquid measure
up the equation
Apothecary System: uses the minim as the basic
unit of liquid measure and the grain as the basic unit
of solid measure
o Minim – liquid measure
o Grain – solid measure
Household System: Measuring system that is found
in recipe books. This system uses the teaspoon as
the basic unit of fluid measure and the pound as the
basic unit of solid measure
o Teaspoon – liquid measure
o Pound – solid measure
Avoirdupois System: iThis system uses
ounces and grains, but they measure differently than
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
PARENTAL DRUGS: All drugs administered
parenterally must be administered in liquid form. The
person administering the drug needs to calculate the
volume of the liquid that must be given to administer the
prescribed dose. The same formula can be used for this
determination that was used for determining the dose of
an oral liquid drug:
Therefore, the nurse would administer two tablets.
Example: An order is written for 0.05 g
spironolactone (Aldactone) to be given orally (per
os, PO). Aldactone is available in 25-mg tablets.
How many tablets would you have to give? First,
you will need to convert the grams to milligrams:
1g=1,000mg
Example: An order has been written for 75 mg of
meperidine (Demerol) to be given intramuscularly. The
vial states that it contains meperidine, 1 mL = 50 mg. Set
up the equation just as before:
Thus, X = 1.5 mL.
INTRAVENOUS DRUGS: Intravenous (IV)
solutions are used to deliver a prescribed amount of fluid,
electrolytes, vitamins, nutrients, or drugs directly into the
bloodstream. Microdrip= 60drops Macrodrip 15drops/mL
Cancel out like units to simplify further: X = 50 mg Most IV delivery systems come with a standard control
called a microdrip, by which each milliliter delivered
So 0.05 g of Aldactone is equal to 50 mg of
contains 60 drops. Macrodrip systems, which usually
Aldactone
deliver 15 drops/mL, are also available; they are usually
used when a large volume must be delivered quickly.
The order has been converted to the same
measurement as the available tablets. Now solve for Always check the packaging of the IV tubing to see how
many drops/mL are delivered by that particular device if
the number of tablets that you will need, letting X
be the number of tablets to equal the desired dose of you have any doubts or are unfamiliar with the system.
50 mg: 4165986471367659 card no. lang 'to ni ate huwag pansinin
That is, the number of drops per minute, or the rate that
you will set by adjusting the valve on the IV tubing, is
equal to the amount of solution that has been prescribed
per hour times the number of drops delivered per
milliliter (mL), divided by 60 minutes in an hour.
ROLLE, NICOLE ADRIENNE
PHARMACOLOGY
Example: An order has been written for a patient to
receive 400 mL of 5% dextrose in water (D5W)
over a period of 4 hours in a standard microdrip
system (i.e., 60 drops/mL). Calculate the correct
setting (drops per minute):
PEDIATRIC CONSIDERATIONS
These methods of determining a pediatric dose take into
consideration the child’s age, weight, or body surface.
Therefore, X = 100 drops/min
Now calculate the same order for an IV set that
delivers 15 drops/mL:
Therefore, X = 25 drops/min
If a patient has an order for an IV drug, the same
principle can be used to calculate the speed of the
delivery.
For Example, an order is written for a patient to
receive 50 mL of an antibiotic over 30 minutes. The
IV set used dispenses 60 drops/mL, which allows
greater control. Calculate how fast the delivery
should be.
Therefore, X = 1 gr.
Alternatively, the calculation could be based on the
child’s weight, using the Clark rule:
This again yields X = 1 gr.
Therefore, X = 100 drops/min.
ROLLE, NICOLE ADRIENNE