Size: 841 kB 25th Aug 2014 Pharmacology Basics

Report
Pharmacology
Basics
Adapted from NurseCE4less.com for Ambercare
Corporation Education Department, 2014
• Describe the role of receptors related to
medications
• Discuss the four components of
pharmacokinetics
• Describe how medications are classified
• Identify medication classifications, actions,
uses, adverse reactions, side effects,
contraindications and implications
OBJECTIVES
• HOW Tylenol knows to go to your head when you have a
headache and to your elbow when you have “tennis
elbow”?
• OR how one or two small tablets containing only 5001000 mg of active drug can relieve a headache or ease the
inflammation from a strained muscle or tendon in a 185
pound athlete?
DID YOU EVER WONDER…?
• Pharmacokinetic Process:
•
•
•
•
Absorption
Distribution
Metabolism
Excretion
Basic principles of
pharmacology includes…
• Medication management help patients by:
• Curing disease or infection, relieving symptoms such as
pain or nausea
• Can also have the reverse effect:
• In terms of:
•
•
•
•
Allergic reaction
Overdose
Adverse reaction
Administering wrong medication
Patient safety is
paramount!
• Medications are distributed throughout the body by the blood
and other fluids of distribution
• Once they (the med) arrives at it’s proper site of action, they
act by binding to receptors, usually located on the outer
membrane of cells or enzymes located within the cell
• Receptors are like biological “light switches” which turn on
and off when stimulated by a drug which binds to the receptor
and activates it
Receptors – function?
• Narcotics (Opioids) – like Morphine bind to receptors in
the brain that sense pain and decrease the intensity of that
perception
• Antiplatelets (ASA); NSAIDs (Advil) or Antipyretics
(Tylenol) bind to an enzyme located in the cells outside
the brain close to where the pain is localized (e.g., hand,
foot, low back, BUT NOT IN THE BRAIN) – thereby
decreasing the formation of biologically-active
substances known as prostaglandins, which cause pain
and inflammation
Receptors
• Food for thought!
• In some instances – a drug’s “site of action” or
“receptor” may actually be something that resides
within the body – but is not anatomically part of the
body –
• i.e., Tums – the site of action is the acid in the stomach
that is chemically neutralized
• However, if you take an OTC (Tagamet, Pepcid) that
INHIBITS stomach acid production – instead of
neutralization of acid, these compounds BIND to and
INHIBIT receptors in the stomach wall responsible for
producing acid!
Receptors
• Antibiotic therapy is another example of a drug that binds
to a receptor that is not part of your body. Abx bind to
portions of the bacterium that is living in the body which
is causing illness.
• Most Abx inhibit an enzyme inside the bacteria that
causes the bacteria to either stop reproducing or to die
from inhibition of a vital biochemical process
Receptors – another
example
• As medical science has learned more about how drugs at,
pharmacologists have discovered that the body is full of
different types of receptors that respond to many different
types of drugs. Some receptors are very selective and
specific, while others lack such specificity and respond to
several different types of drug molecules
Pharmacologist
discoveries
• To date, receptors have been identified for the
following common drugs, or neurotransmitters found
in the body:
• Narcotics (opioids) – Morphine
• Benzodiazepines (Valium, Xanax)
• Acetylcholine (nicotinic and muscarinic cholinergic
receptors) found in the parasympathetic system
(resting/digesting)
• Dopamine, serotonin (sympathetic system)
• Epinephrine (adrenalin) and NE (alpha and beta receptors) –
found in the sympathetic system (fight/flight) of the CNS
and many others….
Receptors – common
drugs
• Neurotransmitters are chemicals
released from the END of ONE
NEURON (nerve cell) which diffuse
across the space between neurons
called the synaptic cleft and stimulate
an adjacent neuron to signal the
transmission of information….
Neurotransmitters
• Pharmacokinetics – what is it? –
a branch of pharmacology which
deals with determining the
movement (kinetics) of drugs into
and out of the body
Pharmacokinetics
• Absorption
• Distribution
• Metabolism
• Excretion
Four scientific or
pharmacokinetic
processes…..
• Is the process by which a drug is made available to the fluids
of distribution of the body (e.g., blood, plasma, serum, aqueous
humor, lymph, etc.).
• In the fasting state, most orally-administered drugs (PO) reach
maximum or “peak” blood concentration within one to two
hours
• IV is the most rapid route of administration, then…
• Intra-nasal
• Inhalation
• SL
• IM
• SC or SQ (in the above order) – route of administration….
Absorption
• Dependent on (PO drugs) – and the subsequent appearance of
the drug in the blood on the following factors:
• Rate of disintegration and dissolution of the pill or capsule in the
stomach or GI tract
• Solubility of the drug (the more soluble, the faster absorption rate)
• The molecular charge of the drug molecule (charged substances
are soluble, but don’t pass through lipid (fat) soluble biologic
membranes well)
• Aqueous (water) solubility vs. lipid (fat) solubility
• The presence or absence of food in the stomach (food delays the
absorption of some drugs and enhances the absorption of others)
Rate of Absorption -
• The presence of any concomitant medication(s) that can
interfere with GI motility (e.g., Reglan increase GI
motility, Aluminum antacids slow motility, atropine or
scopolamine used for ulcers or nausea also slow GI
motility (anticholinergic) keeping some drugs in the
stomach longer – slowing absorption rate; on the flip
side:
• Tagamet, Zantac and Prilosec (Pepcid-AC) DECREASE
gastric acid production thereby INCREASING the rate of
gastric emptying and increasing the rate of absorption..
Rate of Absorption – key
factors
• Once the drug has been absorbed from the stomach
and/or intestines (GI tract) into the blood, it is circulated
to some degree to all areas of the body to which there is
blood flow…this process is distribution (the choo-choo
so to speak)
• Organs with high blood flow (brain, heart, liver, etc.) are
the first to accumulate drugs, while connective tissue and
lesser-perfused organs are last…
Distribution
• The pattern of distribution of drug molecules by different
tissues after the chemical enters the circulatory system
varies. Why? Because of differences in pH, lipid content,
cell membrane function and other individual tissue
factors, most drugs are NOT equally distributed in all
parts of the body
• E.g., ASA acidity influences a distribution patter that is
different from that of an alkaline product such as
amphetamine
Distribution effects
• Is the transformation of the drug molecule into a chemically
related substance that is more easily excreted from the body
(also know as: biotransformation, or detoxification)
• Drug metabolism is the process by which the body breaks
down and converts medication into active chemical substances.
• Drugs can interact with other drugs, food and beverages.
Interactions can lessen or magnify the desired therapeutic
effect of a drug, or may cause unwanted or unexpected side
effects
Metabolism
• The primary site of drug metabolism is the
liver…plays a major role in digestion,
detoxification, and elimination of substances
from the body (ponder of this statement for
moment…consider disease processes such as ES
liver disease – what do you need to consider
when administering drugs that are metabolized in
the liver)?
Metabolism – primary
site
• Enzymes in the liver are responsible for chemically
changing drug components into substances known as
metabolites
• Metabolites are then bound to other substances for
excretion through the lungs, or bodily fluids such as
saliva, sweat, breast milk and urine, or through
reabsorption by the intestines
Metabolism
• Can vary from individual to individual – and drug
dosages that work quickly and effectively in one
individual may not work well for another
• Factors such as genetic disposition, environment,
nutrition and age can influence drug metabolism
• Infants and elderly patients may have a reduced capacity
to metabolize certain drugs and can be at risk for drug
toxicity
Metabolic Rate
• Therapeutic agents like antibiotics and drugs
used for the treatment of high blood pressure,
epilepsy (phenobarbital, Dilantin) pain
(morphine, codeine), anxiety (valium Xanax) are
also metabolized to chemically-related
compounds called metabolites which are excreted
in the urine…
Metabolism
• Diuretics (such as HCTZ) can reduce serum K+ and Na+
electrolyte levels when taken with digoxin and lithium
respectively
• MAOIs antidepressants can cause convulsions and other
serious side effects when used with tricyclic antidepressants
(nortriptyline), SSRIs or sympathomimetic drugs
(amphetamines)
• Antibiotics may reduce the efficiency or oral contraceptives
Drugs that commonly
interact with other meds:
• Medications containing metals, such as antacids with
aluminum additives and iron supplements can reduce the
absorption of tetracycline's and fluoroquinolones
• Drugs that inhibit liver enzyme function – thereby
slowing metabolism include; ciprofloxacin,
erythromycin, fluoxetine, paroxetine and ritonavir. The
therapeutic effect of other medications taken with these
drugs may be amplified – Coumadin should be used with
GREAT caution in patients taking these drugs!
Drugs that commonly
interact with other meds:
• Grapefruit juice inhibits metabolism of many meds;
including: cyclosporines, felodipine, nifedipine,
triazolam and midazolam (to name a few)
• Foods and beverages with tyramines (red wine, malted
beers, smoked foods, dried fruits and aged cheeses) can
cause severe and dangerous elevation in blood pressure
when taken with MAOI inhibitors (antidepressants –
emsam; marplan; nardil; parnate)
Foods and beverages /
drug interactions
• Dairy products (milk, cream) and products containing calcium
can prevent the absorption of antibiotics such as tetracycline,
doxycycline, and ciprofloxacin
• Whole milk with Vitamin D can cause milk-alkali syndrome in
patients taking aluminum hydroxide antacids
• Caffeinated beverages can influence drug metabolism
• Alcohol is a CNS depressant – should not be combined with
other CNS depressants (antipsychotics, antihistamines)
Foods and beverages /
drug interactions
• Is the process by which a drug is eliminated from the
body – by various organs such as the kidney and lungs
and found in many biological fluids like: bile, sweat,
hair, breast milk, or tears. However, the most common is
the urine (excretion of drug)
• In order to determine the rate of excretion of any drug
from the blood, one must first be certain that the entire
drug in the patient’s GI tract has been absorbed (consider
GI patients who’s absorption rate is impaired via their
disease process…)
Excretion
• The amount of time required to eliminate half of the drug from
the body is called the half-life
• Generally, it takes six half-lives to rid the body of 98% of drug
and 10 half-lives to completely eliminate the drug from the
body
• Using these mathematical relationships allows pharmacologists
to determine how often a therapeutic drug should be
administered to a patient or toxicologist to determine a time
interval within which one would test positive for drugs of
abuse
Excretion
• A medication will have a generic name and one or more
trade names – the generic name usually signifies the
medication's chemical derivation. The trade name is a
name chosen by the pharmaceutical company for
purposes of marketing.
• Trade names usually begin with a capital letter and
followed by a trademark
• Generic names generally begin with a lower case letter
Drug Nomenclature
Generic
Trade
ibuprofen
Motrin®
acetaminophen
Tylenol®
benzoyl peroxide
Oxy10®
Examples
• Drugs are classified into different groups according to
their chemical characteristics, structure and how they are
used to treat specific diseases
• Example: Controlled versus Non-controlled; Noncontrolled med is not considered to be a depressant or a
stimulant and is not considered addictive or with a
potential for abuse (OTCs or prescription drug)
Drug Classifications
• Are divided into five
schedules based on their
potential for abuse and
physical and psychological
dependence
Controlled Meds
• Schedule I: drugs that currently do not have accepted
medical use, have a high potential for abuse, and lack
accepted safety measures for use (LSD, peyote, heroin)
• Schedule II: drugs that have medical use and a high
potential for abuse; may cause severe dependence
(morphine, secobarbital, amphetamines (Ritalin),
methadone)
Controlled meds
• Schedule III: drugs used in medical practice with less
potential for abuse than Schedule II drugs; may cause
moderate to low physical dependence or high-psychological
dependence (T3s – Tylenol with codeine; stimulants,
depressants, other classes – ketamine is another example)
• Schedule IV: drugs that have medical use and lower abuse
potential than CIII drugs; tend to cause limited physical or
psychological dependence (diazepam)
• Schedule V: drugs that have medical use and lower potential
for abuse than CIV drugs – (cough syrups containing Codeine)
Controlled Meds
• Enable us to readily identify the
similarities and differences among a large
number of medications; one of the best
ways to master pharmacology is to become
familiar with medication
classifications….let’s review some….
Drug Classifications
Actions
They bind to a-adrenergic receptors
– leading to dilation of peripheral
blood vessels; lowering peripheral
resistance and BP
Uses
HTN, BPH, Raynaud’s – short/longacting agents –(Cardura, Minipress)
Adverse reactions /side effects
Hypotension, nasal congestion,
tachycardia, diarrhea, N/V
Contraindications
MI, CAD, including angina
Implications
K+, Na+, carbon dioxide lab
monitoring - daily #’s; intake/output
data – orthostatic BP’s
Alpha-Adrenergic
Blockers
Actions
Contain magnesium, aluminum,
calcium and a combination of these
compounds. They slow down the
rate of gastric emptying and
neutralize gastric acidity
Uses
Gastritis, peptic ulcer, hiatal hernia
and GERD (aluminum carbonate,
calcium carbonate – tums)
Adverse Reactions & Side Effects
Constipation, diarrhea, flatus,
abdominal distention, alkaluria
Contraindications
Allergy and sensitivity
Implications
Assess epigastric pain, GI symptoms
and renal problems and electrolytes
Antacids
Actions
Nitrates – dilate coronary arteries,
decrease preload/afterload; CCB –
dilate CA, decrease SA/AV node
conduction; BB – decrease HR, thus
decreasing oxygen use
Uses
Angina. CCBs, BBs – HTN and
dysrhythmias (ol’s, nitro, verapamil)
Adverse Reactions & Side Effect
Postural Hypotension, fatigue,
dysrhythmias, HTN, edema, dizziness
Contraindications
Increase ICP, cerebral hemorrhage and
sensitivity
Implications
Monitor for SE / Orthostatic BP;
assess for angina pain
Antianginals
Actions
Inhibit acetylcholine (autonomic NS)
Uses
Many. Some decrease GI, urinary and
biliary motility; GI secretions,
decrease involuntary movement and
relieve N/V; decrease secretions at
EOL; increase HR in emergent
situation; COPD (atropine,
scopolamine)
Adverse Reactions/Side Effects
Dryness of mouth; paralytic ileus,
constipation, urinary
retention/hesitancy) dizziness and Ha
Contraindications
GI or urinary obstruction; narrowangle glaucoma, and myasthenia
gravis
Implications
Monitor urinary and bowel function as
well as vital signs;
Anticholinergics
Action
Prevent clot formation
Uses
MI; PE; DVT; DIC; Afib; and HD
patients (Coumadin, heparin)
Adverse Reactions & Side Effects
Hemorrhage, diarrhea, fever, rash and
blood disorders (leukopenia,
thrombocytopenia)
Contraindications
Bleeding disorders, such as
hemophilia, and leukemia, ulcers,
blood dyscrasias, nephritis,
endocarditis and thrombocytopenia
purpura
Implications
Observe for bleeding (black stools,
ecchymosis); monitor hgb/hct;
PT/INR; PTT; vital signs
Anticoagulants
Actions
To prevent seizures
Uses
Prevent tonic-clonic seizures,
psychomotor seizures, status
epilepticus, petit mal and cortical focal
seizures (Phenytoin, Diazepam)
Adverse reactions & side effects
Bone marrow suppression (can be lifethreatening) GI problems; CNS effects
like confusion, ataxia and slurring of
speech
Contraindications
Allergy or sensitivity to drug class
Implications
Monitor hepatic and renal function,
blood, mental status, blood dyscrasias,
and toxicity – especially StevensJohnson syndrome
Anticonvulsants
Actions
MAOIs – inhibit MAO and thus increase
epinephrine, NE, serotonin and dopamine;
Tricyclic's - block the reuptake of serotonin
and NE in the nerve endings, thus increasing
the actions of both in the nerve
Uses
Depression, nocturnal enuresis in children;
(Sertraline; amitriptyline; bupropion; lithium)
Adverse Reactions & Side Effects
Orthostatic hypotension; dry mouth; dizziness,
drowsiness; urinary retention, HTN, renal failure
and paralytic ileus
Contraindications
BPH; seizure disorders, renal, hepatic and cardiac
disease
Implications
Monitor BPs; mental status; renal/hepatic
function; extrapyramidal symptoms; urinary
retention; withdrawal s/sx with abrupt cessation
Antidepressants
Actions
Lowers blood sugar, K+ and P04;
oral med stimulates B-cells of
pancreas to release insulin
Uses
Diabetes and ketoacidosis; (Insulin,
Glyburide)
Adverse Reactions & Side Effects
Hypoglycemia, hepatotoxicity, allergic
responses
Contraindications
Oral agents are contraindicated for
juvenile diabetes and ketoacidosis
Implications
Monitor CBGs; assess for
hypoglycemia, rotate insulin injection
sites and use human insulin when pork
or beef sensitivity
Anti-Diabetic Meds
Actions
Varying. Some decrease water
content in stool, some slow GI
peristalsis
Uses
Diarrhea; (bismuth, kaolin pectin;
loperamide)
Adverse Reactions & Side Effects
Constipation, paralytic ileus,
abdominal pain
Contraindications
Colitis
Implications
Used for short term therapy (48 hours
or less) monitor electrolytes and bowel
response
Antidiarrheal
Actions
Class I: - decreases any disparity in the
refractory period; increases duration of AP
Class II: slows rate of SA node discharge and
conduction through AV node; decreases HR –
decreasing oxygen demand in myocardium
Class III: increases effective refractory period
and AP duration
Class IV: decreases SA nod discharge; slows
conduction through AV node; inhibits Ca++
across cell
Uses
Atrial and Ventricular arrhythmias (afib, PVCs
and tachycardia, HTN, angina) Digoxin,
procainamide, acebutolol, amiodarone
Adverse Reactions and Side Effects
Hypotension, bradycardia, pro-arrhythmic effects
Contraindications
Various – can be numerous
Implications
Monitor rate and rhythm, BP, K+ dependent
edema, I/Os; eyesight, lung function; kidney
function
Antidysrhythmics
Actions
Decreases Na+, K+ and nutrients in the
cell and increases cell permeability
Uses
Fungal infections such as cryptococcosis,
aspergillsis, histoplasmosis,
coccidiomycosis and candidiasis (Nystatin,
Amphotericin B)
Adverse Reactions & Side Effects
Renal, liver damage and failure,
gastroenteritis, hypoK+, anorexia, N/V
Contraindications
Sensitivity and bone marrow depression
Implications
For IV administration, use a filter, check for
extravasation and protect from light (cover
with foil). Monitor VS, I/O, weight, renal
and hepatic function, HypoK+ and
ototoxicity
Antifungals
Actions
Antagonists of Histamine
Uses
Allergies, pruritus and rhinitis;
decrease N/V; (Benadryl, Allegra,
Claritin, Alavert, Tavist, Zyrtec,
Chlor-trimeton);
Adverse Reactions & Side Effects
Drowsiness, Ha, urinary retention,
blood dyscrasias, thickened bronchial
secretions and GI effects
Contraindications
Sensitivity, asthma, PUD, narrow angle
Glaucoma
Implications
Monitor urinary frequency, respiratory
and cardiac status and for blood
dyscrasias
Antihistamines
Actions
ACEI – dilate arterial and venous
system; suppression of RA I to RA II;
CA Adrenergic: inhibits impulses in CNS
(SNS); decrease in CO, BP and HR
Peripherally Adrenergics: inhibits release
of NE; decreasing sympathetic
vasoconstriction
Vasodilators: decrease BP, HR/CO –
dilate smooth muscle of the arteries;
BB/CCB/Diuretics – discussed later
Uses
HTN, HF, angina and some dysrhythmias
Adverse Reactions & Side Effects
Hypotension, tachycardia, bradycardia,
N/V/Ha
Contraindications
Heart block, hypersensitivity
Implications
Edema, monitor renal function, and HF
Antihypertensives
Actions
Inhibit the growth and/or replication
of susceptible bacteria
Uses
Infection(s) – (PCN, Tetracycline)
Adverse Reactions & Side Effects
D/N/V, bone marrow depression and
anaphylaxis
Contraindications
Hypersensitivity; most ppl allergic to
PCNs are also allergic to
cephalosporin's
Implications
Observe bowel pattern and urinary
output. Monitor renal function, blood
cultures and for signs of super
infection and bleeding; along with
WBCs
Anti-Infectives
Actions
Alkylating agents – interfere with DNA;
Antimetabolites – inhibit DNA synthesis
Antibiotics: - inhibit RNA delay or
inhibiting mitosis
Hormones: - change the effects of
androgens, estrogen, luteinizing hormone
and FSH
Uses
Tumors, lymphoma, leukemia and
Hodgkin’s disease (fluorouracil; cisplatin)
Adverse Reactions & Side Effects
Anemia, thrombocytopenia, leukopenia,
N/V; hair loss, hepatotoxicity,
cardiotoxicity
Contraindications
Sensitivity, liver and renal damage
Implications
Monitor CBC with diff; renal and liver
function tests; I/O; observe for bleeding,
jaundice, dependent edema, breaks in skin
and mucosal inflammation, irritation,
phlebitis with IV route
Antineoplastics
Actions
Cholinergic-block acetylcholine
receptors (blocks PSS)
Uses
Parkinson’s Disease (Levodopa)
Adverse Reactions & Side Effects
Involuntary movement, insomnia, N/V;
orthostatic Hypotension; dry mouth;
numbness and Ha
Contraindications
Sensitivity and narrow angle glaucoma
Implications
Monitor respirations, BP and changes
in mentation
Antiparkinson Agents
Actions
Block dopamine receptors in the brain that
involves psychotic behavior
Uses
Schizophrenia, mania, paranoia, and anxiety; can
be used for unrelieved hiccups, N/V and pedi
behavioral problems and pre-op relaxation
(haldol, lithium)
Adverse Reactions & Side Effects
Extrapyramidal symptoms (dystonia, EPS<
akathisia, and tardive dyskinesia); dry mouth,
photosensitivity, agranulocytosis, hypotension and
life threatening cardiac problems and
laryngospasm
Contraindications
CAD, severe HTN, depression, bone marrow
depression; blood dyscrasias, parkinsonism,
cerebral arteriosclerosis, narrow angle glaucoma
and children less than 12; caution in elderly
Implications
Monitor CBC, LFT’s I/O; BP; dizziness;
palpations, tachycardia; LOC, gait and sleep
patterns
Antipsychotics /
Neuroleptic agents
Actions
Decreases the replication of the
offending bacillus through the
inhibition of RNA or DNA
Uses
Pulmonary TB (Rifampin, Isoniazid,
Rifabutin)
Adverse Reactions & Side Effects
Anorexia, N/V; rash, renal, hepatic and
ototoxic effects
Contraindications
Sensitivity, renal disease; caution with
hepatic disease, pregnancy and
lactation
Implications
Check renal and hepatic status and s/sx
of anemia
Antituberulars
Actions
Antitussives – suppression of the
cough reflect;
Expectorants – decrease in the
viscosity of thick, tenacious
secretions
Uses
Cough – bronchitis, TB, pneumonia,
CF; COPD; (antitussives are used for
non-productive coughs) –
Guaifenesin, codeine)
Adverse Reactions & Side Effects
Dizziness, drowsiness and nausea
Contraindications
Iodine sensitivity, pregnancy, lactation
and hypothyroidism; caution in elderly
and asthma patients
Antitussives and
Expectorants
Implications
Monitor cough and sputum, increase
fluid intake and humidification to thin
secretions
Actions
Interferes with the DNA needed for
viral replication
Uses
HIV, herpes, encephalitis, varicella
zoster encephomyelitis, influenza
(acyclovir, tamiflu)
Adverse Reactions & Side Effects
N/V/D/Ha, anorexia, vaginitis, renal
failure and metabolic encephalopathy
which could be fatal
Contraindications
Caution in pregnancy and lactation;
renal and liver disease and dehydration
Implications
Assess renal and liver functions;
observes for s/sx of infection and
allergic reactions (itching, rash,
urticaria); monitor for blood dysrasias
Antivirals
Actions
Decrease impulse transmission to the
cerebral cortex
Uses
Epilepsy, sedation, insomnia,
anesthesia, (phenobarbital and
secobarbital)
Adverse Reactions & Side Effects
Drowsiness, Nausea, blood dyscrasias
and Steven-Johnson syndrome
Contraindications
Allergy, poor liver function, pregnancy
(cat D). Caution in elderly
Implications
Monitor seizure control, BMP, LFTs;
observe for toxicity – insomnia,
hallucinations, hypotension, pulmonary
constrictions, cold clammy skin,
cyanosis of lips (circumoral) N/V
delirium, weakness)
Barbiturates
Actions
Decreases anxiety by potentiating gaminobutyric acid and other CNS
inhibitory transmitters
Uses
Anxiety secondary to phobic disorders and
other conditions, acute ETOH withdrawal
and pre-op (Diazepam, Clonazepam)
Adverse Reactions & Side Effects
Physical dependence and abuse, dizziness,
drowsiness, OHTN, and blurred vision
Contraindications
Narrow angle glaucoma, infants less than 6
months, lactation (diazepam) and liver
disease (clonazepam); caution in elderly
Implications
Monitor OHTN; HR, LFT’s BMP and signs
of dependency; administer with milk or
food to prevent GI upset
Benzodiazepines
Actions
Selective: block stimulation of B1 receptors
(one heart) in the cardiac smooth muscle with
chronotropic and inotropic effects;
Non-selective: lowers BP (plasma renins are
reduced) w/o reduction in HR or reflex
tachycardia
Uses
HTN, angina and ventricular dysrhythmias
(atenolol, metoprolol, propranolol,)
Adverse Reactions & Side Effects
Ohtn, N/V/D, bradycardia, blood dyscrasias, CHF
and bronchospasm
Contraindications
Hblock, cardiogenic shock and HF; caution in
elderly, COPD an asthma patients; CAD, renal and
thyroid disease patients
Implications
Monitor VS; I/O, Daily #s; renal function, edema,
apical and radial pulse
Beta-Adrenergic Blockers
– BB (ol’s)
Actions
Anticholinergics – inhibit the interaction
of acetylcholine at receptor sites on
bronchial smooth muscle
Uses
Asthma, bronchospasm, COPD, CheyneStokes respirations (albuterol,
aminophylline)
Adverse Reactions & Side Effects
Dyspnea, bronchospasm, anxiety, tremors,
throat irritation, N/V
Contraindications
Narrow angle glaucoma, severe cardiac
disease, tachydysrhythmias and sensitivity;
use caution with HTN, seizure disorders,
pregnancy and lactation, hyperthyroidism
and BPH
Implications
Assess for a therapeutic response (absence
of dyspnea and/or wheezing) and
patient/family education about use of
inhaler
Bronchodilators
Actions
Inhibits the flow of calcium ions across the cell
membrane of cardiac and vascular smooth
muscle, thus relaxing the coronary vascular
smooth muscle, dilating the CA, slowing SA/AV
node conduction, and dilating peripheral
arteries
Uses
Angina, HTN, and dysrhythmias (verapamil,
felodipine)
Adverse Reactions & Side Effects
Dysrhythmias, edema, fatigue, HA and drowsiness
Contraindications
SBP of less than 90 mmHg; Wolff-Parkinson
White Syndrome; 2/3rd degree HB; SSS; and
cardiogenic shock; HF may get worse in the
presence of edema; caution with renal and hepatic
disease
Implications
Monitor BP, HR, RR; administer at bedtime and
before meals
Calcium Channel
Blockers
Actions
Cardiac output and cardiac contractility
are enhanced by making more calcium
available
Uses
HF and tachycardia (digitoxin, digoxin)
Adverse Reactions & Side Effects
Cardiac changes, hypotension, GI blurred
vision, yellowish-green halos and Ha
Contraindications
Hypersensitivity, Vfib, Vtach and carotid
sinus syndrome; caution with electrolytes
imbalance; acute MI; severe respiratory
disease, AV block, renal or liver disease,
hypothyroid and the elderly
Implications
Assess VS, check apical rate for one full
minute – if less 60 hold and notify
physician; monitor BMP; I/O
Cardiac Glycosides
Actions
These medications prevent the destruction of
acetylcholine, thus increasing its concentration,
which enhances the transmission of impulses
Uses
Myasthenia gravis, bladder distention, urinary
distention, and post –op paralytic ileus
(neostigmine, bethanechol)
Adverse Reactions & Side Effects
Bronchospasm, laryngospasm, respiratory
depression, convulsion, paralysis, respiratory
arrest, N/V/D
Contraindications
Renal or intestinal obstruction, cautious with
children, lactation, bradycardia, hypotension,
seizure disorders, bronchial asthma, coronary
occlusion and hyperthyroidism
Implications
Monitor VS, I/O; assess for urinary retention,
bradycardia, bronchospasm, hypotension,
respiratory depression
Cholinergics
Actions
Blocks the ANS acetylcholine
Uses
Prevention of surgical secretions, - (at EOL
also) decrease motility of the urinary,
biliary and GI tracts; reverses NM
blockage; parkinsonism symptoms
secondary to the use of neuroleptic
medications (atropine, scopolamine)
Adverse Reactions & Side Effects
Constipation and dryness of the mouth
Contraindications
GI and GU obstruction, angle closure
glaucoma, myasthenia gravis, and
hypersensitivity; caution with elderly, BPH
and tachycardia patients
Implications
Monitor urinary status; I/O – monitor
dysuria, frequency or retention; observe
constipation, LOC; administer with milk or
food
Cholinergic Blockers
Actions
Glucocorticoids – increase capillary permeability and
suppress the movement of fibroblas and leukocytes,
thereby decreasing inflammation
Uses
Glucocorticoids – decrease inflammation – some are used
for adrenal insufficiency, allergies and cerebral edema
(cortisone, dexamethasone, hydrocortisone, prednisone)
Mineralocorticoids – adrenal insufficiency
Adverse Reactions & Side Effects
Insomnia, euphoria, behavioral changes, PUD, sodium and
fluid retention, hypokalemia, hyperglycemia, and
carbohydrate intolerance (metabolic reactions)
Contraindications
Fungal infections, amebiasis, hypersensitivity, and
lactation. Caution in elderly, children and pregnant
women, diabetes, seizures, PUD, glaucoma, HF, HTN,
impaired renal function ,myasthenia gravis and ulcerative
colitis
Implications
Give with food; monitor CBG, K+; Weight; I/O; plasma
cortisol levels, adrenal insufficiency and for any signs of
infection; mood changes, particular depression
Corticosteroids
Actions
Thiazides and thiazide-like diuretics – slow
reabsorption n the distal tubule, thus increasing
the excretion of sodium and water;
Loop diuretics – inhibit the reabsorption of
Na+ and Chloride in the loop of Henle
Carbonic anhydrase inhibitors – decrease the
sodium-hydrogen ion exchange in the tubule,
thus increasing sodium excretion
Uses
HTN with edema and HF (lasix, HCTZ,
aldactone)
Adverse Reactions & Side Effects
HypoK+; hyperglycemia and hyperuricemia
(mostly with thiazides) blood dyscrasias, aplastic
anemia, volume depletion, and dehydration
Contraindications
Electrolyte imbalances, anuria, dehydration;
caution in elderly and renal or hepatic patients
Implications
K+ supplement may be needed with loop diuretic;
observe for signs of hypokalemia and metabolic
alkalosis; given in am
Diuretics
Actions
Inhibits histamine in the parietal cells,
thereby inhibiting the secretion of gastric
acid secretion
Uses
Gastric and duodenal ulcers, GERD;
(cimetidine, ranitidine)
Adverse Reactions & Side Effects
Thrombocytopenia, neutropenia,
aranulocytosis, aplastic anemia, confusion,
diarrhea and Ha
Contraindications
Hypersensitivity, cautious in children less
than 16 years of age, hepatic or renal
disease, organic brain syndrome, lactation
and pregnancy
Implications
Monitor I/O; creatinine, BUN and gastric
pH; (maintain above 5); give slowly IV over
30 minutes to avoid bradycardia and
administer oral with meals
Histamine H2 Antagonists
Actions
Inhibits lymphocytes
Uses
Prevention of organ transplant
rejection; cyclosporine, azathioprine)
Adverse Reactions & Side Effects
Proteinuria, renal failure, albuminuria,
hematuria, hepatotoxicity, oral candida,
gum hyperplasia, HA and tremors
Contraindications
Hypersensitivity; caution in severe
hepatic or renal disease and pregnancy
Implications
Monitor LFTs and BMP, drug blood
levels; observe for hepatotoxicity,
which can include itching, light
colored stools, jaundice and dark urine;
administer with meals
Immunosuppressant's
Actions
Used to treat and prevent constipation; bulk laxatives
absorb water thus adding bulk to stool;
Lubricants: increase water retention in stool
Stimulants: speed up peristalsis
Saline laxatives – pull water from intestines
Osmotic – enhance peristalsis and increase distention
Stool softeners – reduce surface tension of liquids
within the bowel
Uses
Constipation, bowel prep; (psyllium, colace, mag citrate;
mineral oil, bisacodyl)
Adverse Reactions & Side Effects
Cramping, D/N
Contraindications
Megacolon, abdominal pain, N/V, impaction, GI
obstruction or perforation, gastric retention and colitis;
Implications
Monitor I/O, electrolytes;
Laxatives
Actions
Inhibition of nerve impulse
transmission
Uses
The facilitation of endotracheal
intubation and skeletal muscle
relaxation (surgery/general)
(gallamine, pancuronium)
Adverse Reactions & Side Effects
Apnea, respiratory depression,
bronchospasm, and bradycardia
Contraindications
Hypersensitivity; cautious use with
collagen, thyroid and cardiac disease,
lactation, pregnancy, children < 2;
dehydration, electrolyte imbalances
and myasthenia gravis
Implications
Monitor K+ and Mag+; VS q 15’ until
recovery; I/O; IV doses may be given
over 1-2 min
NM blocking agents
Actions
Decreases prostaglandin synthesis
Uses
Mild to moderate pain, arthritis and
dysmenorrhea (Ibuprofen, Naproxen)
Adverse Reactions & Side Effects
Blood dyscrasias, nephrotoxicity
(oliguria, azotemia, hematuria and
dysuria) abdominal pain, cholestasis
hepatitis, anorexia, dizziness and
drowsiness
Contraindications
Asthma, severe liver and/or renal disease,
hypersensitivity. Caution in elderly,
children, lactation, pregnancy and for
patients with GI, cardiac and/or bleeding
disorders
Implications
Monitor renal and hepatic function.
Obtain baseline hearing and eye exams;
toxicity may include: tinnitus and or
blurred vision
NSAIDs
Actions
Depression of the pain impulse
transmission at the level of the spinal
cord
Uses
Moderate to severe pain (Codeine,
fentanyl, morphine, oxycodone)
Adverse Reactions & Side Effects
GI (constipation, n/v; anorexia, cramps);
sedation, respiratory depression;
circulatory depression and increased
ICP
Contraindications
Upper airway obstruction, bronchial
asthma, addiction, hypersensitivity.
Caution with: renal, hepatic, respiratory
and cardiac disease
Implications
Monitor RR; urinary/GI output; LOC;
can be used as antiemetic for N/V;
continue to monitor/assess for pain
Opioid analgesics
Actions
Antipyretic (inhibits the heat regulation center
in the hypothalamus), anti-inflammatory,
analgesic (inhibits prostaglandin),
Uses
Mild to moderate pain, inflammation (arthritis),
fever, and thromboembolic disorders (ASA,
salsalate)
Adverse Reactions & Side Effects
Rash, GI symptoms, hepatotoxicity, blood
dyscrasias, hearing problems (tinnitus) a sign of
possible toxicity
Contraindications
Hypersensitivity; contraindicated with Vit K
deficiency, GI bleed; bleeding disorders; children
with Reye’s syndrome; caution: Hodgkin's;
hepatic/renal failure, anemia
Implications
Monitor renal/hepatic function; observe for
hepatotoxicity (clay colored stools, dark urine,
diarrhea, yellow sclera, itching, fever, abd. Pain
tinnitus
Salicylates
Actions
Convert plasminogen into plasmin to
break down the fibrin of clots
Uses
PE, DV and arterial thrombosis; MI, AV
cannula occlusion (Streptokinase,
urokinase)
Adverse Reactions & Side Effects
Anaphylaxis, GI, GU, IC retroperitoneal
bleeding; most common are decreased HCT,
urticaria, Ha and N
Contraindications
Hypersensitivity; CNS neoplasms, bleeding,
renal or hepatic disease, HTN, COPD,
subacute bacterial endocarditis, rheumatic
VHD, cerebral embolism or thrombosis or
hemorrhage and recent surgery
Implications
Monitor VS and LOC; monitor bleeding
(temp >104); arrhythmias, retro bleed;
allergic response; ecchymosis, hematuria,
hematemesis, epistaxis; not effective if
thrombi are more than 1 wk old. Use 0.8
mm filter with IV administration
Thrombolytics
Actions
Increase metabolism, C/O, blood
volume, 02 consumption and RR
Uses
Thyroid replacement (thyroid,
levothyroxine)
Adverse Reactions & Side Effects
Palpitations, tachycardia, insomnia,
tremors, angina, #loss, dysrhythmias,
thyroid storm
Contraindications
MI, adrenal insufficiency and
thyrotoxicosis; caution in elderly,
pregnant and lactating moms; DM,
HTN, angina and cardiac disease
Implications
Administer at same time every day;
monitor BP; I/O; #; cardiac status,
irritability, excitability and nervousness
Thyroid medications
Actions
Various – decreases vascular
resistance and increases blood flow
Uses
HTN, angina, intermittent claudication,
vasospasm, arteriosclerosis Imdur,
Ismo (isosorbide mononitrate),
Hydralazine, Isosorbide Dinitrate (SR);
minoxidil; Nipride, Nitro-bid
Adverse Reactions & Side Effects
Hypotension, HTN, changes in EKG,
Nausea, Ha
Contraindications
Tachycardia, acute MI, thyrotoxicosis;
PUD, uncompensated heart disease
Implications
Administer with meals to reduce GI
s/sx; monitor bleeding times and
cardiac status
Vasodilators
• The topic of pharmacology is an important one for all
involved in the filed of healthcare. Medications have
great power to help patients, but can also harm them.
Having an understanding of the basics of will allow
clinicians to better serve their patients
SUMMARY

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