Saturday, July 7, 2018

NURSING: PHARMACOLOGY Review Notes


PHARMACOLOGY

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

Safety and Efficacy
Nursing Principles :
 1. Always verify the Five Rights .
        a. the right medications
        b. the right client
        c. the right dosage
        d. the right form, route and technique  
        e. the right time
 2. Chart drug administration only after its 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 :
     a. immediately notify the nursing supervisor, the prescribing physician, and the
         pharmacist.
     b. 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)
 3. Topical – skin, inhalants, mucus membrane.
     

  Eye medications :
  - administer eyedrops first then ointment.
  - use a separate bottle for each client.
  - instruct the client to tilt the head backward, open  eyes and look up.
  - avoid contact of medication bottle to the eyeball.
  - place prescribed dose in the lower conjunctival sac.
  - instruct the client  to press the inner canthus  for 30-60 seconds.
  - instruct the client to close the eye gently.


 Ear drops
   - in infant and children younger than 3 y.o, pull pinna downward and backward.
   - in older children and adult, upward and  backward.
   - direct the solution on the wall of the ear canal, not directly on the ear drum.


CLASSIFICATIONS OF DRUGS

  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.
 Indications :
    - 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 client’s in cool environment.
  2. Watch out for signs of heatstroke and dehydration.
  3. Encourage clients to increase fluid intake and  use of sugarless gum/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, phenylephrine,
      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,
                           dark-colored 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.

              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
         (gamma-amino 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.
  6. Rotate and don’t shake the ampules of  barbiturates.  Don’t mix with other drugs.
  7. 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 metabolize 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.


      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 :
- lignocaine + prilocaine (EMLA cream) should be  applied topically 60 minutes before
  procedure.
- administer cautiously to the areas of large broken skin.
- 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.

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 .
Text Box:      HEMOSTASIS :
          
         Bleeding/injury                                                  
                  I
       Vasoconstriction                                                     Plasminogen
                I                                                                              I             
        Platelet aggregation                                                    Plasmin
        ( temporary plug)                                                             I  
                 I                                                                               I
      Clotting factor activation --------------                                  I
                I                                          I                                           I
 Intrinsic pathway (8,9,10,11,12)   Extrinsic pathway  (3,7,10)     I
              (PTT )                                   (PT)  Vit K dep.               I
                  I                                             I                                  I         
                    I   Prothrombin activation    I                             I
                                I                                                       I        
                           Thrombin                                       I
                                I                                    I
      Fibrinogen ------------Fibrin threads ------------- Fibrin split products
                                     (coagulation)          ( Removed by liver & spleen )
   

     - 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)

 
THROMBOLYTICS
  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 :
    -  monitor bleeding
    -  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 :
   - Monitor bleeding time ( NV = 1-9 mins)
   - 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 :
  -  Monitor for toxicity as evidence by :
         nausea, vomiting, anorexia, halo vision, confusion, bradycardia and heart blocks .
  - Do not administer if pulse is less than 60 bpm.
  - Should be caution in patient with hypothyroidism and hypokalemia.
  - Antidote : Digi-bind
  - Phenytoin is the drug of choice to manage
    digitalis-induced arrhythmia.
Nitrates
  Prototype :
      - isosorbide 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 mins.  for a total of three doses; if not relieved
       after 15 mins., 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 actions :
 - interfere with cholesterol synthesis as well as
   decreasing lipoprotein & triglyceride synthesis.
  Nursing considerations :
  - monitor liver functions while using statins.
  - prevent constipation, flatulence, cholelithiasis
  - encourage increase fluid and fiber intake.


ANTI – HYPERTENSIVE

Angiotensin-Converting Enzyme (ACE) Inhibitors
  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 :
     - not to discontinue medications because it can cause rebound hypertension.
     - 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 promote vasodilatation of the coronary and peripheral vessels.
  Indications :
   - hypertension, angina, arrhythmia
  Adverse effects :
   -  bradycardia, hypotension, headache
   -  reflex tachycardia, constipation
  Nursing considerations :
   - Administer between meals to enhance  absorption.
   - Take client’s pulse rate before each dose,  withhold if pulse is below 60 bpm.
   - Refer for signs of congestive heart failure.



 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 reabsorb K
     - hyperkalemia




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 :
   - Contraindicated hyperthyroidism, cardiac dysrhythmia, or uncontrolled seizure
      disorder.
   - 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 :
  - Take drugs at meal time or with food.
  - Eat foods high in potassium, low in sodium.
  - Instruct client to avoid individuals with RTI.
  - Instruct client not to stop medication abruptly, it should be tapered to prevent
     adrenal insufficiency
  - Avoid taking NSAID while taking steroids.
  - 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:
  - Should be given before asthmatic attacks.
  - Administer oral capsule at least 30 mins before meals for better absorption.
  - Drink a few sips of water before & after inhalation to prevent cough & unpleasant taste
  - Assess for lactose-intolerance.

  ANTI-HISTAMINES (H-1 BLOCKERS)
   Protoytype :
   - 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 :
   - Administer with food and drink.
   - Given IM via Z-track method or orally.
   - Precautions in handling machine and driving while taking these drugs.
   - 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 are 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.



  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 :
  - Give 1 hr after meals.
  - Avoid giving medications within 1-2 hrs of  antacid administration
                 (decreases absorption).
  - Take fluids to flush after intake of antacid suspensions.
  - 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 :
   - Given before or with meals
   - Avoid giving other drugs with cimetidine
   - Gynecomastia may developed 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 :
   - Given before meals preferably at morning.


 Mucosal Barriers
   Prototype :
     - sucralfate (Carafate), misoprostol (Cytotec).
   Mechanism of action :
     - coats the mucosa to prevent ulcerations.
   Nursing consideration :
     - Given before meals.
     - Misoprostol is contraindicated for pregnants.
     - 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 :
   - Monitor for rebound constipation.
   - Be cautious taking if with infectious diarrhea.
   - Monitor atropine toxicity with diphenoxylate.
   - 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 :
      - Consult poison control center before induction of vomiting.
     - Administer  ipecac syrup with large amount of fluid.

     DRUGS AFFECTING THE   ENDOCRINE SYSTEM

  THYROID AGENTS
   Prototype :
    - Proloid (thryroglobulin )
    - Synthroid (levothyroxine)
    - Cytomel ( liothyronine).
   Mechanism of action :
    - function as natural or synthetic hormones.
   Nursing considerations :
    - Taken in the morning.
    -  Caution with coronary artery disease.
    -  Monitor for signs of hyperthyroidism and   refer for decreasing the dose.


 PARATHYROID AGENTS
  Prototype :
    a. calcitonin (Calcimar), etidronate (Didronel),
    b. calcitrol (Rocaltrol), calcifediol (Calcedrol)
  Mechanism of action :
    a. reduce bone resorption
    b. promotes calcium absorption
  Nursing considerations :
    - Monitor signs of calcium imbalance
    - Report for bone pains.
    - Remain sitting upright after taking etidronate. 
















Oral Hypoglycemic Agents  (OHA)
1. Sulfonylureas
     -  stimulate insulin secretions and  increase tissue sensitivity to insulin.
 First Generation :
   Chlorpropamide (Diabenese)
     -  disulfiram precautions
   Tolbutamide (Orinase)
     -  congenital defect
 Second Generation :
        Glypizide, Glymepiride
2. Biguanides
      - facilitates insulin action on the  peripheral  receptor site.
         Metformin and Glucophage (Glucovance)
          - side effect is lactic acidosis
3. Alpha-glucosidase inhibitors
     - delay carbohydrate absorption in the intestinal system.
         Acarbose (Precose) – side effect is diarrhea
4. Thiazolinidine
     - increase tissue sensitivity of insulin.
         Rosiglitazone (Avandia)
  5. Meglitinides
   - stimulate insulin release in pancreatic B-cells.
   Repaglinide (Prandin)

Nursing considerations :
   - Effective only for type II DM.
   - Contraindicated to pregnant & breastfeeding.
   - Given before meals.
   - Monitor for signs of hypoglycemia.




 Insulin
   Insulin                                   Onset       Peak      Duration

Immediate-acting                    0.15h      0.5–1h           5 h
            (lispro)
Short-acting                          0.5-1 h     2-4 h              5-7h
(regular, semilente)
Intermediate-acting                 1-3 h     6-12 h 18-24 h
            (NPH, lente)
Long-acting                                4-6h    10-30 h         24-36 h
            (ultralente)
Mixed                                        0.5 h           4-8 h             25 h
(regular 30%, NPH 70%)
Nursing considerations :
  - Usually given before meals.
  - Roll the bottle in palm of hands, don’t shake.
  - Inject amount of air that is equal to each dose
     into the bottle – short acting last (clear).
  - Aspirate short acting first, then long or   intermediate (cloudy).
  - Alcohol is recommended for cleansing bottle but not with skin.
  - Pinch skin, avoid I.M, don’t aspirate.
  - Rotate the injection site an inch a part.
  - Prefilled syringes are stored vertically, needle-up.
  - May increase dose during illnesses.
  - Used bottles stored in room temperature, unused bottle stored in refrigerator.
  - Monitor for acute hypoglycemia :
       a. 3-4 commercially prepared glucose tablet
       b. 4-6 ounce of fruit juice or regular soda
       c.  2-3 teaspoon or honey
       d. Glucagon 1 gm SQ or IM
       e. D50-50 IV.



ESTROGENS AND PROGESTINS
  Prototype :
    - conjugated estrogen (Premarin), estrone  (Bestrone),  estradiol (Estrace),
      diethylstilbestrol (DES).
  Indications :
    - prostate cancer, contraceptions
    - estrogen replacement
  Adverse effects :
   estrogen - endometrial CA, gallbladder disease, HPN, migraine, breast tenderness
   progesterone - altered menstrual flow, risk of   thrombo embolism
 Nursing considerations :
 1. Mix estrogen or progestins prior to IM administration by rolling vials between palms.
 2. Monitor blood pressure
 3. Teach patient how to perform BSE.
 4. Regular follow-up examination is required to detect associated risk of acquiring CA

           









DRUGS AFFECTING  LABOR and LACTATION
  

Uterine Stimulating Agents
 Protoytpe :
 a. Oxytocin (Pitocin), ergonovine (Ergotrate), methylergonovine (methergine)
 b. carbopost (Prostin), dinoprostone (Prostin E2)
 Mechanism of actions :
 a. stimulates uterine smooth muscles
 b. ripening of cervix
 Adverse reactions :
 - fetal bradycardia (oxytocin),
 - hypertension (ergonovine), palpitations
 - allergic reactions (Prostaglandins)



 Uterine Inhibiting Agents (Tocolytic)
  Prototype :
   - ritodrine (Yutopar), terbutaline (Brethine)
  Mechanism of actions :
   - relaxes the uterus by stimulating the B2- adrenergic receptors
  Adverse effects :
-          tremors, nausea, vomiting and tachycardia



 Lactation Suppressants
   Prototype :
    - bromocriptine (Parlodel)
   Mechanism of action :
    - decrease serum prolactin levels
  Adverse effects :
   - drowsiness, headache, nausea, palpitations
  


   DRUGS FOR TREATING  INFECTION

 Antibacterial Agents
 1. Cell wall inhibitors
     a. penicillins - pen G, amoxicillin, cloxacillin
     b. cephalosphorins - cephalexin, cefaclor
     c. glycopeptide - vancomycin
 2. Protein synthesis inhibitors
     a. aminoglycosides - amikacin, gentamycin
     b. macrolide - erythromycins, roxithromycin
     c. lincosamides -  clindamycins
     d. chloramphenicol, tetracyclines
 3. Antimetabolites - blocks folic acid synthesis
    a. Sulfonamides - cotrimoxazole
4. DNA synthesis inhibitors
    a. quinolones - ciprofloxacin, ofloxacin
    b. metronidazole
 Adverse effects :
  1. Aminoglycoside - nephrotoxicity & ototoxicity
  2. Sulfonamides - Steven-Johnson’s syndrome, photosynsetivity
  3. Quinolones - insomnia
  4. Tetracyclines - bone problems
  5. Chloramphenicol -  Gray syndrome, bone marrow depression
  6. Erythromycin - hepatitis

 Nursing considerations :
  1. Collect appropriate specimen for C & S before starting antibiotics.
  2. Check client’s history of allergies.
  3. Avoid administering erythromycin and  quinolones with food.
  4. Pregnant precautions.
  5. Report for diarrhea - pseudomembranous  colitis (clindamycin)
  6. Monitor adverse effects.
 

 Antiviral Agents
   Prototype :
    - acyclovir (Zovirax), ganciclovir (Cytovene),
      vidarabine (Vira-A), amantidine (Symmetrel),
      ribavirin (Virazole), zidovidine (Retrovir).
  Mechanism of actions :
    - inhibits virus specific enzymes involve in DNA
      synthesis. They only control the growth of
      virus but it does not cure.
  Adverse effects :
   - granulocytopenia, thrombocytopenia, nausea,
     nervousness, headache, nephrotoxicity.


Nursing consideration :
  - Pregnant and breastfeeding precautions.
  - Administer IV antivirals to avoid crystallization in renal tubules.
  - Give ribavirin only with aerosol generator.
  - Monitor CBC and creatinine level.
  - Refer for signs of bleeding.
  - Take amantidine after meals.


 Antifungal Agents
  Prototype :
   - amphotericin B (Fungisone), nystatin,
     fluconazole (Diflucan), ketoconazole (Nizoral).
  Mechanism of actions :
   - inhibit the synthesis of fungal sterol.
  Adverse effects :
   - nephrotoxicity and neurotoxicity
   - bone marrow depression
   - chills, fever, joint pains, abdominal pain and headache.
 Nursing considerations :
  - Dilute amphotericin B with sterile water solution not with electrolyte solution.
  - Tell clients that fever, chills, GI upset, joint and muscle pain will subside as
     amphotericin B continues.
  - With oral candidiasis, let nystatin tablet dissolve in mouth rather than swallowing it.
  - Refrain ketoconazole with antacids.
  - Report for signs of bleeding, infection &  fatigue.
 

 ANTIPARASITIC AGENTS
  Prototype :
  a. Antimalarial
       - chlroquine, mefloquine, primaquine,
         quinine, pyrimethamine
  b. Antiamebiasis
       - metronidazole (Flagyl), iodoquinol,
         furozolidone (Furoxone).
  Mechanism of actions :
  a. antimalarial – alters protozoal DNA, depleting  folates, & reducing nucleic acid
                             production
  b. antiamoeba – block protein synthesis.
 Nursing considerations :
 1. Administer anti-malarial drugs with food.
 2. Take seizure precautions while administering
      antimalarial drugs.
 3. Refer cinchonism during quinine treatment:
      - tinnitus, headache, vertigo, fever, and   visual changes.
 4. Inform clients that iodoquinol falsify thyroid function test for up to 6 months.



 ANTIHELMINTIC
  Prototype :
    - mebendazole (Vermox), thiabendazole,
      niclosamide (Niclocide), piperazine (Antepar),
      praziquantel (Biltricide).
  Mechanism of actions :
    - paralyze larva and adult helmints by acting on parasite microtubules.
  Adverse effects :
    - GI upset, urinary odor (thiabendazole)
    - headache, dizziness, fatigue
 Nursing considerations :
  1. Treat all the family members for nematodes infection to prevent recurrence.
  2. Praziquantel  must swallowed rapidly because  of its bitter taste to avoid gagging.
  3. Other antihelmintics should be chewed.


ANTI-NEOPLASTIC DRUGS

 General considerations :
  - kills or inhibit the reproduction of neoplasmic  cells but as well as normal cells.
  - it could be cell cycle phase specific or cell cycle non-specific.
  - preferably given through IV route.


 Prototype :
  1. Alkylating Agents
        - inhibits cell production by causing  cross linking of DNA
      a. Busulfan – hyperuricemia
      b. Chlorambucil – gonadal suppression
      c. Cisplatin – ototoxicity and nephrotoxicity
      d. Cyclophosphamide – hemorrhagic cystitis.
  2. Antitumor Antibiotic Agents
        - interfere in DNA and RNA synthesis
      a. Plicamycin – affects bleeding time
      b. Doxurubicin – cardiotoxicity
      c. Bleomycin – pulmonary toxicity.


 3. Antimetabolites
      - replace normal proteins required for DNA  synthesis by inhibiting the S phase
     a. Cytarabine – hepatotoxicity
     b. 5-flourouracil – phototoxicity reaction and  cerebellar dysfunctions
     c. 6-marcaptopurine – hyperuricemia
     d. Methotrexate – photosensitivity
                     - given with leucoverin to lessen its toxicity.
 4. Mitotic Inhibitors (Vinca Alkaloids)
      - prevent mitosis acting on the M phase  causing cell death
     a. Vincristine sulfate – neurotoxicity, numbness
 5. Hormonal Medications and Enzymes
      - block the normal hormones in hormone sensitive tumors
   a. Tamoxifen citrate – visual problems
         – elevate cholesterol & triglycerides level
    b. Diethylstilbestrol – impotence and gynecomastia in men.

Side Effects:
  stomatitis
     - bland diet, avoid strong mouthwash
     - soft tooth brush, ice chips
  diarrhea, nausea and vomiting
     - anti-emetic, replace fluids and electrolytes
  alopecia
     - reassure that it is temporary
     - encourage o wear wigs, hats and head scarf
  skin pigmentation
     - inform that it is only temporary
  tumor lysis syndrome
     - hyperuricemia & hyperkalemia
     - force fluids
  infection
     - notify physician if WBC is <2000/mm3
     - monitor for signs of infection
     - reverse isolation
     - low bacteria diet
  anemia
     - iron, B-12, folic acid rich food
     - provide rest periods
  bleeding
     - avoid NSAIDs
     - minimize invasive procedures
     - use soft toothbrush and electric razor
  menstrual changes
     - reassure that menstruation will resume.    

                                                           THE END

For Pharmacology Practice Exam, Click the link below
Pharmacology Practice Exam
http://zipansion.com/24mnF

No comments:

Post a Comment