37669948-Pharmacology-A-Review

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PHARMACOLOGY: A REVIEW
PHARMACOLOGY
- most simply defined as study of drug.
Fundamentals of Pharmacology
1. Pharmacokinetics
- study of drug’s changes as it enters and passes through the body.
a. absorption
b. distribution
c. biotransformation
d. excretion
2. Pharmacodynamics
- mechanism by which drugs produce changes in body tissue.
a.
desired effect - intended action of drugs
b.
adverse effect - harmful unintended reactions
c.
side effects – consequence reactions
d.
toxicity – the degree which something is poisonous
 Digoxin = 0.5 – 2.0 ng/mL
 Lithium = 0.5 – 1.5 mEq/L
 Digoxin Toxicity: nausea, vomiting, anorexia, diarrhea, halo vision
SAFETY AND EFFICACY
Nursing Principles
1. Always verify the Five Rights
a. Right Medication
b. Right Amount
c. Right Patient
d. Right Manner and Route
e. Right Time
f. Right Documentation
g. Right Assessment
h. Right Education
i. Right Evaluation
j. Right to Refuse to Medication
2. Chart drug administration only after it has been given, never before.
3. Never leave the medication on cart or tray unattended.
4. Chart observed therapeutic and adverse effects accurately and fully.
5. Check history for allergies and potential drug interactions before
administering a newly ordered drug.
6. Inform the prescribing physician of any observed adverse effects; if
cannot be located, inform the nursing supervisor
7. Question drug orders that are unclear, that appear to contain errors,
or that have potential to harm.
8. Take the following actions if an error occurs: immediately notify the
nursing supervisor, the prescribing physician, and the pharmacist. Assess
the client’s condition and provide any necessary care.
9. For postpartum women, advice to take drugs after breastfeeding.
Administration of Drugs
Routes and Nursing Considerations:
1. Enteral – oral, sublingual, rectal, gastric tubes
-capsulated pill, sustained release and enteric coated should not be
crushed.
2. Parenteral – IV, IM, SQ, ID, IT, IA, epidural.
 Vastus lateralis (safest site for IM)
 Deltoid- less than 2ml
 Dorsogulteal (gluteus maximus)- not use for patient less than 3 years
old
3. Topical – skin, inhalants, mucus membrane.
Eye medications
o administer eyedrops first then ointment.
o use a separate bottle for each client.
o instruct the client to tilt the head backward, open eyes and look up.
o avoid contact of medication bottle to the eyeball.
o place prescribed dose in the lower conjunctival sac.
o instruct the client to press the inner canthus for 30-60 seconds.
o instruct the client to close the eye gently.
Ear drops
o in infant and children younger than 3 y.o, pull pinna downward and
backward.
o in older children and adult, upward and backward.
o direct the solution on the wall of the ear canal, not directly on the ear
drum.
CLASSIFICATIONS OF DRUGS
A. DRUGS AFFECTING THE CENTRAL AND AUTONOMIC SYSTEM
Cholinergic Agents (Parasympathomemitics)
Prototype
-synthetic acetylcholine, pilocarpine, carbachol, bethanecol (Urocholine),
edrophonium (Tensilon), neostigmine (Prostigmine), pyridostigmine
(Mestinon).
Mechanism of action
-stimulates cholinergic receptors by mimicking acetylcholine or inhibition
of enzyme cholinesterase
Indications
-glaucoma, urine retention, Myasthenia Gravis
-antidote to neuromuscular blocking agents : tricyclic antidepressants
and atropine
Adverse effects
-blurring of vision, miosis
-increase in salivation, intestinal cramps
-bronchoconstriction, wheezing, DOB
-hypotension and bradycardia
Nursing considerations
1. Warn & monitor clients of the side effects
2. Have atropine available for use as antidote
Cholinergic Blocking Agents (Parasympatholytics,
Anticholinergics)
Prototype
-atropine, scopalamine (Triptone), dicyclomine (Bentyl), propantheline
(Pro-Banthine).
Mechanism of actions
-block the binding of acetylcholine in the receptors of parasympathetic
nerves.
Indication
-use preoperatively to dry up secretions.
-treat spasticity of GI or urinary tract.
-use for treatment of bradycardia, asthma, Parkinsonism.
-use for antidote in organophosphate poisoning.
Adverse effects
-dry mouth, dilatation of pupils, tachycardia
-urinary retention, ileus, heat stroke
Nursing considerations
1. Keep clients in cool environment.
2. Watch out for signs of heatstroke and dehydration.
3. Encourage clients to increase fluid intake and use of sugarless
um/candy for dry mouth.
4. For GI spasticity, administer 30 minutes before meals and at bed
time.
Adrenergic Agents (Sympathomimetics)
Prototype
-epinephrine, norepinephrine, ephedrine, dopamine, dobutamine,
henylephrine, terbutaline, albuterol, isoproterenol.
Mechanism of actions
-stimulate alpha and beta adrenergic receptor directly or trigger the
release of catecholamines indirectly causing sympathetic effects.
Indications
-cardiopulmonary arrest, hypotension
-COPD and asthma, nasal congestions
-allergic reaction, anaphylactic shock
Adverse effects
-restlessness, insomnia, tremors, nausea
-palpitations, angina, tachycardia, HPN
Nursing considerations
1. Contraindicated in clients w/ hyperthyroidism, pheochromocytoma &
cardiovascular disease.
2. Monitor vital signs and advice precautions.
3. Should be taken with food.
Adrenergic Blocking Agents
Prototype
a. Alpha blockers
-phentolamine (Regintine), phenoxybenzamine, prazosin (Minipress),
reserpine (Serpasil), terazosin (Hytrin)
-clonidine (Catapress), methyldopa (Aldomet)
b. Beta blockers
-atenolol (Tenormin), esmolol (Brevibloc), metoprolol (Lopressor),
nadolol (Corgard), propanolol (Inderal), timolol ( Blocadren)
Mechanism of actions
a. alpha blockers
-inhibits action of a-receptors in vascular smooth muscle to cause
vasodilatation.
b. beta blockers
-compete with epinephrine in b-receptors in heart, pulmonary airways,
peripheral circulation and CNS.
Indications
-Raynaud’s disease, hypertension, pheochromocytoma.
-angina, arrhythmias, mitral valve prolapse, glaucoma
Adverse effects
-orthostatic hypotension, bradycardia, CHF
-depression, insomnia and vertigo
-bronchospasm and dyspnea, nasal stuffiness, cold extremities
Nursing considerations
1. Administer oral alpha-blockers with milk to minimize GI side effects.
2. Administer oral beta-blockers before meals and at a.m. if insomnia
occurs.
3. Check client’s apical pulse rate before drug administration, refer if
below 60 bpm.
4. Hypotensive precautions.
5. Warn clients not to drive or operate dangerous machinery until
he/she has adjusted to medications.
Skeletal Muscle Relaxants Agents
Prototype
-methacarbamol (Robaxin), baclofen (Lioresal), dantrolene (Dantrium),
metaxalone (Skelaxin), orphanedrine (Norgesic), chlorzoxazone
Mechanism of actions
-depress CNS
-inhibit calcium ion release in the muscle
-enhance the inhibitory action of GABA (gamma-amino butyric acid)
Indications
-for acute musculoskeletal pain
-for muscle spasticity associated with multiple sclerosis, cerebral palsy,
CVA, and spinal cord injury
Adverse effects
-hypotonia, ataxia, hypotension, drowsiness
-blurred vision, bradycardia, depression, urine retention
Nursing considerations
1. Caution clients that mental alertness may be impaired.
2. Monitor neuromuscular status, bowel and bladder functions.
3. Inform clients that maximum benefit of baclofen is attained for 1-2
months.
4. Reduce baclofen dosage gradually because of associated withdrawal
symptoms: Confusion, hallucinations, paranoia & rebound spasticity.
Anticonvulsants
Prototype
a. Hydantoins-phenytoin (Dilantin)
b. Barbiturates-phenobarbital ( Luminal)
c. Miscellaneous
- carbamazepine (Tegretol), diazepam, clorazepate (Tranxene),
valproic acid (Dapakene), ethosuximide (Zarontin)
Mechanism of action
-treat seizures by depressing abnormal neuronal activity in motor cortex
Adverse effects
-sedation & drowsiness, gingival hyperplasia
-diplopia, nystagmus, vertigo, dizziness
-thrombocytopenia, aplastic anemia
Nursing considerations
1. Advise female clients to use contraceptives.
2. Inform clients taking phenytoin that harmless urine discoloration is
common.
3. Warn clients with diabetes that hydantoins may increase blood sugar
level and that valproic acid may produce a false positive result in urine
ketone test.
4. Teach clients receiving carbamazepine to identify symptoms of bone
marrow depressions.
5. Reassure that barbiturates are not addictive at a low dosage.
6. Avoid taking alcohol with barbiturates.
7. Administer IV phenytoin slowly to avoid cardiotoxicity.
8. Avoid mixing other drugs in same syringe with phenytoin.
Antiparkinsonian Agents
Prototype
a. Anticholinergic agents
-trihexyphenidyl (Artane), benztropine (Congentin)
b. Dopaminergic agents
-Levodopa, carbidopa-levodopa (Sinemet), amantidine (Symmetrel),
pergolide (Permax), selegiline (Eldepryl), bromocriptine.
Mechanism of actions
a. anticholinergic agents
-inhibit cerebral motor centers
b. dopaminergic agents
-increasing dopamine concentrations or enhancing neurotransmitter
functioning.
Adverse effects of dopaminergic agents
a. levodopa–nausea, vomiting, anorexia, orthostatic hypotension, darkcolored urine and sweat
b. amantidine–ankle edema, constipation
c. bromocriptine–palpitations, tachycardia
Nursing considerations
1. Give dopaminergic agents after meals to reduce GI symptoms.
2. Reassure client that levodopa may cause harmless darkening of urine
and sweat.
3. Avoid taking Vit B6 (pyridoxine) with levodopa because it speed up
metabolism.
4. Educate clients to minimize orthostatic hypotension.
5. Elevate leg to reduce ankle edema.
Central Nervous System Stimulants
Prototype
-amphetamines, methylphenidate (Ritalin)
Mechanism of actions
-increase excitatory CNS neurotransmitter activity and blocks inhibitory
impulses
Indications
-for obesity (amphetamines)
-attention deficit hyperactivity disorders
-narcolepsy
-drug-induced respiratory depressions.
Adverse effects
-nervousness, insomnia, restlessness
-hypertension, tachycardia, headache
-anorexia, dry mouth
Nursing considerations
1. Should be given at morning.
2. Don’t stop amphetamine abruptly to avoid withdrawal symptoms.
3. Monitor blood pressure and pulse.
4. Ice chips or sugarless gum for dry mouth.
5. Watch out for growth retardation in children taking methylphenidate
B. DRUGS AFFECTING MENTAL FUNCTIONING
Sedatives, Hypnotics, and Anxiolytics
Prototype
a. Benzodiazepines
-diazepam (Valium), lorazipam (Ativan), alprazolam (Xanax),
flurazepam (Dalmane)
b. Barbiturates
-amobarbital, phenobarbital, secobarbital
c. Miscellaneous
-chloral hydrate (Noctec), buspirone (Buspar), paraldehyde (Paral)
Mechanism of actions
a. Benzodiazepines
-increase the effect of inhibitory neuro transmitter GABA (gammaamino butyric acid)
b. Barbiturates and Miscellaneous agents
-depress CNS
Indications
-induce sleep, sedate and calm clients
Adverse effects
-hangover-effect, dizziness, CNS depression
-respiratory depression, drug-dependence
Nursing considerations
1. Warn clients of injuries and falls.
2. Brief period of confusion and excitement upon waking up is common
with benzodiazepines.
3. Warn clients not to discontinue medications abruptly without
consulting a physician.
4. Avoid alcohol while taking these drugs.
5. Rotate and don’t shake the ampules of barbiturates. Don’t mix with
other drugs.
6. Warn female clients that diazepam is associated with cleft lip.
Antidepressants and Mood Disorder Drugs
Prototype
a. Tricyclic antidepressants
-amitriptyline (Elavil), protriptyline (Vivactil), imipramine (Tofranil),
desipramine
b. MAO (monoamine oxidase inhibitors)
-isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine
(Pernate)
c. Second-generation antidepressants
-fluoxetine (Prozac), trazodone (Desyrel)
d. Lithium
Mechanism of actions
a. Tricyclic antidepressants
-increase receptor sensitivity to serotonin and/or norepinephrine.
b. MAO inhibitors
-inhibit the enzyme MAO that metabolizes the neurotransmitters
norepinephrine and serotonin.
c. Second – generation antidepressants
-inhibits the reuptake of serotonin.
d. Lithium
-increase serotonin & norepinephrine uptake
Adverse effects
-dry mouth, blurred vision, urine retention, constipation (anticholinergic
effects)
-orthostatic hypotension, insomnia
-hypertensive crisis (MAO)
-dehydration (Lithium)
Nursing considerations
1. Caution client to rise slowly to reduce the effects of orthostatic
hypotension.
2. Take antidepressant with food to enhance absorption
3. Explain to client that full response may take several weeks (2
weeks).
4. Assess client for constipation resulting from tricyclic antidepressant
use.
5. Client taking MAO inhibitors should avoid tyramine-rich foods to
avoid Hypertensive crisis.
-aged cheese, sour cream, yogurt, beer, wine, chocolate, soy sauce and
yeast
-pentholamine (Regintine) is the drug of choice for hypertensive crisis.
6. Inform physician and withhold fluoxetine if client develop rashes.
7. Take lithium with food to reduce GI effects
->1.5 mEq/L blood level may cause toxicity manifested by: confusion,
lethargy, seizures,hyperreflexia.
-maintain salt and adequate fluid intake
-tremors may occur but it is temporary
-monitor white blood cell count (increase)
Antipsychotic drugs (Neuroleptics)
Prototype
a. Phenothiazines
-chlorpromazine (Thorazine),
-trifluoperazine (Stelazine),
-thioridazine (Mellaril)
b. Other Agents
-clozapine (Clozaril), haloperidol (Haldol)
Mechanism of action
-block dopamine receptor in the limbic system, hypothalamus, and other
regions of the brain.
Adverse effects
-Extra pyramidal symptoms such as dystonia, pseudoparkinsonism, and
an irreversible tardive dyskinesia as manifested by :
a. lip smacking
b. fine wormlike tongue movement
c. involuntary movements of arms and leg.
-Neuroleptic malignant syndrome
a. fever, tachycardia, tachypnea, diaphoresis, cardiovascular collapse
b. muscle rigidity, seizures.
-orthostatic hypotension
Nursing considerations
1. Teach family members the signs of EPS and NMS, and report to
physician immediately.
2. Normalization of symptoms may not occur for several weeks after
beginning of therapy.
3. Avoid administering haloperidol intravenously
4. Watch out of neutropenia with clozapine.
5. Watch out for orthostatic hypotension and photosensitivity with
phenothiazine.
6. Be sure that oral doses are swallowed, and not hoarded.
C. DRUGS USED IN PAIN MANAGEMENT
General Anesthetics
Prototype
a. Inhalation anesthetics
-enflurane (Ethrane), halothane
-isoflurane (Forane), nitrous oxide
b. Injection anesthetics
-fentanyl (Sublimaze), ketamine (Ketalar), thiopental Na (Penthotal),
etomidate (Amidate)
Mechanism of actions
-cause CNS depression, by producing loss of consciousness,
unresponsiveness to pain stimuli, and muscle relaxation
Nursing considerations
1. Instruct client NPO for 8 hours before administration.
2. Monitor cardio pulmonary depression and hypotension.
3. Monitor urinary retention.
4. Monitor body temperature
-malignant hyperthermic crisis: dantrolene (antidote)
5. Avoid alcohol or CNS depressants for 24 hours after anesthesia
6. In patient who received halothane, monitor signs of hepatic fatal side
effects:
-rash, fever, nausea, vomiting
-jaundice and altered liver function
Local and Topical Anesthetic
Prototype
Local: bupivacaine, lidocaine, tetracaine, procaine, mepivacaine,
prilocaine
Topical: benzocaine, butacaine, dibucaine,lignocaine
Mechanism of action
-block transmission of impulses across nerve cell membrane.
Adverse effects
-cardiac dysrhythmias
Nursing considerations
1. lignocaine + prilocaine (EMLA cream) should be applied topically 60
minutes before procedure.
2. administer cautiously to the areas of large broken skin.
3. observe for fetal bradycardia in pregnant clients.
Analgesics
Prototype
a. Narcotic analgesics
-codeine, meperidine (Demerol) morphine, butorphanol (Stadol)
nalbuphine (Nubain)
b. Non – narcotic analgesic
NSAIDs – aspirin (aminosalicylic acid), mefenamic acid (Ponstan),
ibuprofen (Motrin), naproxen, ketoprofen (Orudis), ketorolac.
paracetamol and acetaminophen (Tylenol)
Mechanism of actions
a. Narcotic analgesics
-alter pain perception by binding to opiod receptors in CNS
b. Non- narcotic analgesic
-relieves pain and fever by inhibiting the prostaglandin pathway.
Nursing considerations
1. Monitor respiratory depression & hypotension in clients taking
narcotic analgesic.
2. Injury and accident precautions in clients taking narcotic analgesic.
3. Warn clients about possibility of dependency, and do not discontinue
narcotics abruptly in the narcotic-dependent clients.
4. Naloxone is antidote for narcotic overdose.
5. Advice clients to take NSAIDs with food and monitor bleeding
complications.
6. Aspirin is contraindicated in clients below 18 years old with flu-like
symptoms.
7. Monitor hearing loss in clients taking aspirin.
8. Monitor liver function in clients taking acetaminophen.
9. N-acetylcysteine is antidote for paracetamol overdose.
D. DRUGS AFFECTING THE CARDIOVASCULAR SYSTEM
Anticoagulants
Prototype
-Heparin (SQ and IV), Warfarin (Orally)
Mechanism of actions
a. Heparin
-prevents thrombin from converting fibrinogen to fibrin.
b. Warfarin
-suppress coagulation by acting as an antagonist of vitamin K after 4-5
days.
Indications
-thrombosis, pulmonary embolism, myocardial infarction
Adverse effect
-bleeding
Nursing considerations
1. HEPARIN sodium
-if given SQ don’t aspirate or rub the injection site (above the scapula best site).
-therapeutic level 1.5-2.5 times normal PTT; normal PTT is 20-35 sec.
= 50-85 sec.
-antidote: (protamine sulfate)
2. WARFARIN sodium (coumadin)
-warfarin is used for long-term
-onset of action is 4-5 days.
-therapeutic level is 1.5-2.5 times normal PT; normal PT = 9.6 -11.8
sec. = 25 - 30 sec; INR = 2 – 3
-should be taken at the same time of the day to maintain at
therapeutic level.
-reduce intake of green leafy vegetables.
-antidote: Vitamin K (Aquamephyton)
Hemostasis:
Bleeding/injury
I
Vasoconstriction
Plasminogen
I
I
Platelet aggregation
Plasmin
(temporary plug)
I
I
I
Clotting factor activation ---------------------------I
I
I
I
I
Intrinsic pathway (8, 9, 10, 11, 12)
Extrinsic pathway (3, 7, 10) I
I
I
I
(PTT)
(PT) Vit K depletion
I
`
I
I
I
Prothrombin activation
I
I
I
Thrombin
I
I
I
I
Fibrinogen ------------Fibrin threads ------------- Fibrin split products
(Coagulation)
(Removed by liver & spleen)
Thrombolytic
Prototype
Streptokinase, Urokinase
Mechanism of actions
-activates plasminogen to generates plasmin (enzyme that dissolve
clots).
Indications
-use early in the course of MI (within 4-6 hours of the onset)
Nursing considerations
1.
monitor bleeding
2.
antidote : Aminocarpic acid
Antiplatelet Medications
Prototype
Aspirin, Dipyridamole (Persantin), Clopidoigrel (Plavix), Ticlopidine
Mechanism of action
-inhibit the aggregation of platelet thereby prolonging bleeding time.
Indications
-used in the prophylaxis of long-term complication following M.I,
coronary revascularization, and thrombotic CVA.
Nursing considerations
1. Monitor bleeding time (NV = 1-9 mins)
2. Take the medication with food.
Cardiac Glycosides
Prototype
-digoxin (Lanoxin) and digitoxin (Crystodigin)
Mechanism of actions
-increase intracellular calcium, which causes the heart muscle fibers to
contract more efficiently, producing positive inotropic & negative
chronotropic action.
Indications
-use for CHF, atrial tachycardia and fibrillation
Nursing considerations
1. Monitor for toxicity as evidence by : nausea, vomiting, anorexia, halo
vision, confusion, bradycardia and heart blocks .
2. Do not administer if pulse is less than 60 bpm.
3. Should be caution in patient with hypothyroidism and hypokalemia.
4. Antidote : Digi-bind
5. Phenytoin is the drug of choice to manage digitalis-induced
arrhythmia.
Nitrates
Prototype
-sosorbide dinitrate (Isordil)
-nitroglycerine (Deponit, Nitrostat)
Mechanism of action
-produce vasodilatation including coronary artery.
Indications
-angina pectoris, MI, peripheral arterial occlusive disease
Adverse effects
-headache, orthostatic hypotension
Nursing Considerations
1. Transdermal patch
-apply the patch to a hairless area using a new patch and different
site each day.
-remove the patch after 12-24 hours, allowing 10-12 hours “patch
free” each day to prevent tolerance.
2. Sublingual medications
-note the BP before giving the medication
-offer sips of water before giving because dryness may inhibit
absorption
-one tablet for pain and repeat every 5 minutes for a total of three
doses; if not relieved after 15 minutes seek medical help.
-stinging or burning sensation indicates that the tablet is fresh.
-instruct patient not to swallow the pill
-sustained release medications should be swallowed and not to be
crush
-protect the pills from light
Anti-arrhythmic Drugs
Class I (block Na channels)
IA - quinidine, procainamide
IB – lidocaine
IC - flecainamide
Class II (Beta-blockers)
propanolol, esmolol
Class III (block K channels)
amiodarone, bretylium
Class IV (block Ca channels)
verapramil, diltiazem
Nursing considerations
1. Watch out for signs of CHF.
2. Have client weigh themselves and report weight gain.
3. Watch out for signs of lidocaine toxicity: confusion and restlessness
Antilipemics
Prototype
a.cholesterol-lowering agents
-cholestyramine, colestipol, lovastatin
b.triglyceride-lowering agents
-gemfibrozil, clofibrate
Mechanism of action
-interfere with cholesterol synthesis as well as decreasing lipoprotein &
triglyceride synthesis.
Nursing considerations
1. monitor liver functions while using statins.
2. prevent constipation, flatulence, cholelithiasis
3. encourage increase fluid and fiber intake.
E. ANTI – HYPERTENSIVE MEDICATIONS
Angiotensin-Converting Enzyme (ACE) Inhibitors “PRIL”
Prototype
captopril (Capoten), enalapril (Vasotec), quinapril, lisinopril
Mechanism of actions
-prevent peripheral vasoconstriction by blocking conversion of
angiotensin I to angiotensin II decreasing peripheral resistance
Adverse effect
-it cause hyperkalemia
-induce chronic cough
Nursing considerations
1. not to discontinue medications because it can cause rebound
hypertension.
2. avoid using K+ sparing diuretics.
Calcium-Channel Blockers
Prototype
-Nifedipine (calcibloc, adalat), Amlodipine (norvasc), Felodipine (Plendil)
Verapramil (Isoptin)
Mechanism of action
-decrease cardiac contractility and the workload of the heart, thus
decreasing the need for O2.
-it also promotes vasodilatation of the coronary and peripheral vessels.
Indications
-hypertension, angina, arrhythmia
Adverse effects
-bradycardia, hypotension, headache
-reflex tachycardia, constipation
Nursing considerations
1. Administer between meals to enhance absorption.
2. Take client’s pulse rate before each dose, withhold if pulse is below
60 bpm.
3. Refer for signs of congestive heart failure.
F. DIURETICS
-usually given at morning
Carbonic Anhydrase Inhibitors
-Acetazolimide (Diamox)
-Increase Na+, K+, & Hco3 Secretion, Along With It Is H2o
-Metabolic Acidosis
Osmotic Diuretic
-Mannitol
-Increase Osmotic Pressure Of The Glomerular Filtrate.
-Hypotension
Thiazide Diuretics
-Hydrochlorothiazide
-Blocks Na and K Reabsorption; Reabsorb Ca
-Hypercalcemia
Loop Diuretics
-Furosemide (Lasix)
-Blocks Na, K, and Ca Reabsorption
-Hypocalcemia
Potassium Sparing Diuretics
-Spironolactone (Aldactone)
-Excrete Na and Water but it reabsorbs K
-Hyperkalemia
F. RESPIRATORY MEDICATIONS
Bronchodilators
Prototype:
Symphatomimetic
Xanthines
-albuterol, salbutamol
-aminophylline
-isoproterenol, salmeterol
-theophylline
-terbutaline
Mechanism of actions:
-sympathomimetic (b-receptor agonist) bronchodilators, dilate airways.
-xanthine bronchodilators, stimulate CNS for respiration.
Indications:
-bronchospasm, asthma, bronchitis, COPD
Adverse effects:
-palpitations and tachycardia
-restlessness, nervousness, tremors
-anorexia, nausea and vomiting, headache, dizziness
Nursing considerations:
1. Contraindicated hyperthyroidism, cardiac dysrhythmia, or
uncontrolled seizure disorder.
2. It should be used with caution in patient with HPN and narrow-angle
glaucoma.
Glucocorticoids (Corticosteroids)
Prototype:
-dexamethasone, budesonide, fluticasone, prednisone, beclomethasone
Mechanism of actions:
-act as anti-inflammatory agents and reduce edema of the airways, as
well as pulmonary edema.
Adverse effects:
-Cushing’s syndrome, neutropenia. osteoporosis
Nursing considerations:
1. Take drugs at meal time or with food.
2. Eat foods high in potassium, low in sodium.
3. Instruct client to avoid individuals with RTI.
4. Instruct client not to stop medication abruptly, it should be tapered
to prevent adrenal insufficiency
5. Avoid taking NSAID while taking steroids.
6. Take inhaled bronchodilators first before taking inhaled steroids, and
rinse mouth after using.
Mast Cell Stabilizers
Prototype:
-cromolyn sodium (Intal)
Mechanism of action:
-stabilize mast cells that release histamine triggering asthmatic attacks.
Nursing Consideration:
1. It should be given before asthmatic attacks.
2. Administer oral capsule at least 30 mins before meals for better
absorption.
3. Drink a few sips of water before & after inhalation to prevent cough
& unpleasant taste
4. Assess for lactose-intolerance.
Anti-histamines (H-1 blockers)
Prototype:
-Astemizole (Hismanal), Loratidine (Claritin), Brompheniramine
(Dimetapp), Diphenhydramine (Benadryl), Cetirizine (Iterax),
Celestamine (Tavist)
Mechanism of action:
-decrease nasopharyngeal secretions and decrease nasal itching by
blocking histamine in H1-receptor.
Indications:
-common colds, rhinitis, nausea and vomiting, urticaria, allergies and as
sleep aid
Nursing Considerations:
1. Administer with food and drink.
2. Given IM via Z-track method or orally.
3. Precautions in handling machine and driving while taking these
drugs.
4. Ice chips or candy for dry mouth
Anti-tuberculosis
Prototype:
First line
Second line
-Isoniazid (INH)
-Cycloserine
-Rifampicin (Rifadin)
-Kanamycin
-Ethambutol
-Ethonamide
-Pyrazinamide
-Para-aminosalicylic acid
-Streptomycin
-active tuberculosis is treated with drug combination for 6-9 mos.
-multidrug-resistant strain (MDR-TB) are medicated for 1 year up to 2
years
-given before meals
Isoniazid
-should be given 1 hr before or 2 hrs after meals because food may
delay absorption.
-should be given at least 1 hr before antacids.
-instruct to notify physician for signs of hepatoxicity (jaundice), and
neurotoxicity, numbness of extremities.
-administer with Vitamin B6 to counteract the neurotoxic side effects.
-avoid alcohol.
Rifampicin
-given on an empty stomach with 8 0z. of water, 1 hour before or 2
hours after meals and avoid taking antacids with medications.
-hepatotoxic thus avoid alcohol.
-instruct the client that urine, feces, sweat, and tears will be red-orange
in color.
Pyrazinamide
-given for 2 months.
-increase serum uric acid and cause photosensitivity.
Ethambutol
-contraindicated in children under 13 years old.
-obtain a baseline visual acuity because it can cause optic neuritis.
-instruct the client to notify the physician immediately if any visual
problems occurs.
Streptomycin
-aminoglycoside antibiotic given IM
-nephrotoxic and ototoxic
-obtain baseline audiometric test and repeat every 1-2 months because
the medications impairs the CN VIII
G. DRUGS AFFECTING GASTROINTESTINAL SYSTEM
Antacids
Prototype:
-Aluminum/magnesium compounds (Maalox)
-Sodium bicarbonate (Alka-Seltzer)
-Calcium carbonate (Tums)
-Magnesium hydroxide (Milk of Magnesia).
Mechanism of actions:
-neutralize the stomach acidity.
Adverse effects:
-metabolic alkalosis, stone formation
-electrolyte imbalance
-diarrhea (magnesium), constipation (aluminum)
Nursing considerations:
1. Give 1 hr after meals.
2. Avoid giving medications within 1-2 hrs of antacid administration
(decreases absorption).
3. Take fluids to flush after intake of antacid suspensions.
4. Monitor for changes of bowel patterns.
Histamine – 2 blockers
Prototype:
-cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid),
nizatidine (Axid)
Mechanism of action:
-blocks H2 receptors in the stomach, reducing acid secretions
Nursing considerations:
1. Given before or with meals
2. Avoid giving other drugs with cimetidine
3. Gynecomastia may develop with chronic use of cimetidine.
Proton – Pump Inhibitors (PPI)
Prototype:
-omeprazole (Losec), Lansoprazole (Lanz), pantoprazole (Pantoloc).
Mechanism of action:
-inhibit the proton H+ to combine with Cl- toform hydrochloric acid.
Nursing considerations:
1. Given before meals preferably at morning
Mucosal Barriers
Prototype:
-sucralfate (Carafate), misoprostol (Cytotec).
Mechanism of action:
-coats the mucosa to prevent ulcerations
Nursing consideration:
2. Given before meals
3. Misoprostol is contraindicated for pregnants.
4. Sucralfate cause constipation.
Anti-diarrheal Agents
Prototype:
-diphenoxylate (Lomotil), loperamide (Imodium), kaolin/pectin mixture
(Kaopectate)
Mechanism of actions:
-decrease stomach motility and peristalsis
Nursing considerations:
1. Monitor for rebound constipation.
2. Be cautious taking if with infectious diarrhea.
3. Monitor atropine toxicity with diphenoxylate.
4. Clay, white or pale stool is common with kaopectate.
Laxatives
A. lactulose (Cephulac), Na biphosphate (Fleet enema) & magnesium salt
(Milk of Magnesia)
-retain fluid and distend intestine
B. ducosate (Dialose)
-emulsify fecal fat and water
C. bisacodyl (Dulcolax) & senna (X-prep)
-irritates intestinal mucosa and stimulate intestinal smooth muscles
D. bulk-forming laxative (Metamucil)
-increase fecal bulk and water content
E. mineral oil
-lubricates & prevent colon absorption
Emetics
Prototype:
-ipecac syrup, apomorphine
Mechanism of actions:
-induce vomiting through stimulation of vomiting center of medulla.
Indications:
-ingestion of poisonous or toxic substances
Nursing considerations:
1. Consult poison control center before induction of vomiting.
2. Administer ipecac syrup with large amount of fluid.
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