Respiratory Drugs

Question 1

what is the pleural cavity?

Answer 1

potential space existing around each lung
negatively pressurized at all times

Question 2

what does narrowing of airway cause?

Answer 2

increased airflow and more irritation and reflex bronchoconstriction

Question 3

what is the main active stimulator of bronchoconstriction and secretion?

Answer 3

parasympathetic input

Question 4

what does sympathetic input cause?

Answer 4

bronchodilation
beta2

Question 5

what are the positives of inhalation therapy?

Answer 5

achieves high local concentrations
may minimize systemic exposures and hence adverse effects

Question 6

what are the main disadvantages of inhalation therapy?

Answer 6

ensuring accurate dose is delivered
knowing what the dose should be in the first place

Question 7

what class of drugs is used as antitussives?

Answer 7

opiates

Question 8

when should you not use an antitussive?

Answer 8

productive cough and/or bacterial pneumonia

Question 9

how do opioid antitussives reduce the cough?

Answer 9

decrease responsiveness of cough center to afferent stimuli and may decrease peripheral response of sensory nerve endings
mu and kappa receptors

Question 10

what opioid antitussives do we use?

Answer 10

butorphanol
hydrocodone
codeine
diphenoxylate and atropine

Question 11

what effects does butorphanol have?

Answer 11

weak analgesic
effective cough suppressant

Question 12

what receptors does butorphanol impact?

Answer 12

partial mu receptor agonist and full kappa receptor agonist

Question 13

is dextromethorphan an opioid?

Answer 13

no: structurally related to but does not bind opioid receptors

Question 14

what receptors does dexstromethorphan stimulate?

Answer 14

sigma-1 receptors

Question 15

which antitussive do we use in cats?

Answer 15

dextromethorphan is safest

Question 16

what is the mechanism of action for mucolytics?

Answer 16

breakdown mucous secretions

Question 17

what is the mechanism of action for expectorants?

Answer 17

increase bronchial secretions
enhance mucociliary clearance
promote productive cough

Question 18

what is one mucolytic?

Answer 18

acetylcysteine

Question 19

how does acetylcysteine work?

Answer 19

interacts with disulfide bonds on mucoproteins to break down mucous
enhances mucous clearance
increases glutathione

Question 20

why is acetylcysteine used as an anti-dote for some toxicants?

Answer 20

increases glutathione concentrations or reacts directly with toxic metabolites

Question 21

what is the predominant system for control of bronchiole tone?

Answer 21

parasympathetic

Question 22

what is the primary adrenergic receptor for control of bronchiole tone?

Answer 22

beta-2

Question 23

what are the actions of beta-2 agonist bronchodilators?

Answer 23

smooth muscle relaxation
decrease release of inflammatory mediators from mast cells
decrease and thin secretions
increase mucociliary clearance (activate cilia)

Question 24

what does chronic stimulation of beta-2 receptors result in?

Answer 24

down-regulation and de-sensitization of receptors

Question 25

what enhances response to beta-2 agonists?

Answer 25

corticosteroids

Question 26

what does down-regulation and de-sensitization of beta-2 receptors lead to?

Answer 26

variable response to beta-2 agonists

Question 27

what can peripheral beta-2 activation lead do?

Answer 27

vasodilation hypotension reflex tachycardia

Question 28

who is clenbuterol approved in?

Answer 28

horses banned in food animals: was used as tocolytic and growth promotant

Question 29

which species is terbutaline preferred for?

Answer 29

cats injectable

Question 30

what is the mechanism of action of theophylline?

Answer 30

adenosine receptor antagonist inhibits phosphodiesterase (increase cAMP) augments release of catecholamines

Question 31

what do methylxanthines cause?

Answer 31

airway smooth muscle relaxation decreased release of inflammatory mediators from mast cells increased mucociliary transport

Question 32

in what can methylxanthines be used?

Answer 32

occasionally feline asthma cardiogenic cough in dogs: enlarged left atrium pushes on bronchi collapsing trachea in dogs

Question 33

what are respiratory stimulants used for?

Answer 33

decrease respiratory depressant effects of opiates and barbituates "dummy" foals to correct hypercapnea

Question 34

what does doxapram do?

Answer 34

stimulates respiratory center activates aortic/carotid chemoreceptors

Question 35

what do mast cell stabilizers do?

Answer 35

stabilize mast cells and prevent release of inflammatory mediators may inhibit platelet-activating factor (early and late phases of pulmonary inflammatory response)

Question 36

what do glucocorticoids do?

Answer 36

upregulate beta-adrenergic receptors and increase their sensitivity: increase synthesis of intermediary protein in second messenger system of receptors

Question 37

what is the clinical use of mast cell stabilizers?

Answer 37

must be administered prior to triggering exposure

Question 38

the lungs are found within the ___________ cavity, not the ______________________

Answer 38

thoracic pleural cavities

Question 39

_____________________ can increase sensitivity to nociceptors, leading to bronchoconstriction, and increase secretions, thereby narrowing airways

Answer 39

inflammatory mediators histamine, prostaglandins, leukotrienes

Question 40

what are the sites of action of drugs affecting the respiratory system?

Answer 40

lung tissue alveoli/bronchioles/bronchi pleural cavity/space membranes autonomic nervous system CNS: cortex and cough center

Question 41

what must you use for aerosol drugs?

Answer 41

metered-dose inhaler products with an appropriate spacer

Question 42

what do we want to do with inflammatory/allergic airway diseases?

Answer 42

decrease inflammation/immune response promote air exchange by increasing bronchi and bronchiole diameter improve mucociliary clearance

Question 43

what classes of drugs do we use in inflammatory/allergic airway diseases?

Answer 43

anti-inflammatories bronchodilators

Question 44

what do we use in exercise-induced pulmonary hemorrhage?

Answer 44

diuretics

Question 45

what are antitussives used for primarily in horses?

Answer 45

diagnostic procedures equine asthma

Question 46

what is the cough reflex?

Answer 46

afferent nerve endings in bronchi and trachea: irritation and stretch, vagus nerve activate cough center in medulla oblongata

Question 47

what is the response in opioid antitussives?

Answer 47

inconsistent significant adverse effects

Question 48

what might hydrocodone come with?

Answer 48

homatropine: prevent human abuse antimuscarinic effects

Question 49

which hydrocodone products should you not use?

Answer 49

those with acetaminophen in them

Question 50

what is the detailed mechanism of action for mucolytics (acetylcysteine)?

Answer 50

interacts with disulfide bonds on mucoproteins to break down mucous enhances mucous clearance increases glutathione

Question 51

with beta 2 agonists, what might non-selective agonists do?

Answer 51

activate beta 1 and cause tachycardia and arrhythmias

Question 52

what activity does terbutaline have?

Answer 52

beta 2 agonist minimal beta 1 activity

Question 53

can you use terbutaline orally in horses?

Answer 53

no low bioavailability

Question 54

can you use the racemic mixture of albuterol chronically in cats?

Answer 54

no S-isomer pro-inflammatory

Question 55

what is theophylline/aminophylline?

Answer 55

adenosine receptor antagonist: bronchodilation, respiratory stimulation

Question 56

what do methylxanthines stimulate?

Answer 56

respiration centrally diaphragmatic contractions CNS excitement/toxicity

Question 57

what will happen if respiratory stimulants are over-used?

Answer 57

loss of stimulatory effect and loss of respiration

Question 58

what is cromolyn?

Answer 58

mast cell stabilizer may inhibit platelet activating factor

Question 59

how long do glucocorticoids take in dogs to have an effect on upregulating beta-adrenergic receptors and increasing their sensitivity?

Answer 59

48 hours