Week 11- Drugs for the airway 1 and 2

Question 1

what is acute infectious tracheobronchitis

Answer 1

• common urt disease
• caused by multiple infectious agents

Question 2

how does acute infectious tracheobronchitis present

Answer 2

• acute onset hacking cough
• often history of recent exposure to other dog
• clinically bright, active, eating
• lung auscultation normal or sightly harsh upper airway sounds
• cough may be induced on tracheal pinch

Question 3

How might you treat acute infectious tracheobronchitis?

Answer 3

• Restrict exercise
• avoid access to airborne pollutants or irritants
• give wet food

Question 4

What vaccination is given for acute infectious tracheobronchitis?

Answer 4

• live strain of canine parainfluenza and bordatella
• Vaccinated animals can spread B.bronchisepta vaccine strain for a few weeks and the canine parainfluenza vaccine strain for a few days after vaccination

Question 5

What is an antitussive drug?

Answer 5

Drugs that suppress coughing
* Demulcents
* Centrally acting opiates

Question 6

What kinds of drugs might you give for a respiratory disease?

Answer 6

• Antitussive drugs
• Decongestants/ mucolytics
• Bronchodilators
• Drugs to reduce airway inflammation

Question 7

What is the main function of an antiussive/ when are they used?

Answer 7

• they decrease the frequency of coughing
• treat painful non-productive coughing
• or when coughing may cause further injury

Question 8

What is the function of a demulcent?

Answer 8

• such as honey or syrup
• coat and soothe inflamed tissues
• provide brief periods of relief from mild stimulus

Question 9

what supresses the medullary cough centre in low doses

Answer 9

centrally acting opiates

Question 10

What do mucolytics stimulate?

Answer 10

• Increase in fluid secretion by the mucus glands of the resp tract and break down the network of acid glycoprotein fibres found in mucoid sputum

Question 11

How does bronchodilation occur?

Answer 11

Activation of muscarinic
receptors causes contraction
of airway smooth muscle ->
bronchoconstriction
So we want to block with
a muscarininc receptor
antagonist

Question 12

What is ipatropium bromide?

Answer 12

• long-acting
• given once a day
• via inhalation
• used for RAO in horses

Question 13

What is salbutamol used for?

Answer 13

predominantly stimulates B2 receptors causing an increase in cyclic AMP

Question 14

What is clenbuterol used for?

Answer 14

• highly selective for the beta 2 adrenoceptor
• provides intense bronchodilating properties
• minimal effect on the cardiovascular system

Question 15

What animals is clenbutarol licensed for treatment in?

Answer 15

Licensed in horses for treatment of respiratory disease where the airway obstruction is due to bronchospasm and/ or accumulation of mucus

Question 16

What is theophylline?

Answer 16

Similiar in structure to caffeine and theobromine
* relaxes smooth muscle, relieves bronchospasm

Question 17

What is the mechanism of action of theophylline?

Answer 17

Mechanisms of action are thought to include inhibition of
phosphodiesterase enzyme, alteration of intra-cellular calcium,
catecholamine release and adenosine and prostaglandin antagonism
* Also dilates coronary arteries and increases the strength of
contraction of the myocardium. Acts on kidney to induce diuresis and
is a potent stimulant of the CNS

Question 18

What is the function of mast cell stabilisers?

Answer 18

Sodium cromoglycate inhibits mast cell degranulation of histamine on antigen challenge and may also have membrane stabilising properties

Question 19

What are the main effects of glucocorticoids?

Answer 19

exogenous glucocorticoids (e.g. prednisolone, dexamethasone,
beclomethasone H, fluticasone H) inhibit the transcription of genes
responsible for the production of mediators involved in airway inflammation
(cytokines, chemokines, adhesion molecules)
* Manage exacerbations and establish control with prednisolone /
dexamethasone
* Maintain patients on inhaled beclomethasone H / fluticasone H
* Prolonged release steroid, methylprednisolone, useful for cats with asthma

Question 20

What is the function of B-lactam antibiotics?

Answer 20

inhibit bacterial growth by
interfering with the transpeptidation of bacterial wall synthesis - bactericidal

Question 21

What is amoxicllin?

Answer 21

Broad spectrum penicillin effective against gram +ve bacteria and gram -ve bacteria

Question 22

What is clavulanate potassium?

Answer 22

irreversible inhibitor bacterial B-lactamases and prevents hydrolysis of amoxicllin

Question 23

What is the function of tetracyclines?

Answer 23

they inhibit protein synthesis in susceptible bacteria (bacteriostatic)
good lung penetration

Question 24

What is trimethoprim?

Answer 24

folate antagonist- bacteriostatic

Question 25

What is trimethoprim often combined with?

Answer 25

sulphonamides

Question 26

What is the mechanism of action for antifungals?

Answer 26

• highly selective binding for fungal cytochrome P-450
  isoenzymes. Inhibit the synthesis of ergosterol, which is essential component
  of cell membranes for fungi. Also affect membrane-bound enzyme function
  and membrane permeability, resulting in structural degeneration of the fungus