Drugs And The Respiratory System

Question 0

Examples of centrally mediated respiratory dysfunction ….

Answer 0

Premature birth
Opioid intoxication
Rest syndrome

Question 1

Examples of classic lung diseases …

Answer 1

Asthma
COPD
Pulmonary oedema
Cystic fibrosis

Question 2

What is asthma ?

Answer 2

Chronic inflammatory disease of the airways causing bronchospasm and dyspnea

Question 3

What happens in an asthma attack ?

Answer 3

Smooth muscle in bronchial cell walls contract constricting airways so breathing is difficult

Question 4

What are common triggers of asthma ?

Answer 4

Allergens, rapid changes in temp, drugs and exercise

Question 5

What are the symptoms of asthma ?

Answer 5

Feeling of breathlessness
Tight chest
Wheezing
Cough- especially at night

Question 6

How is asthma diagnosed ?

Answer 6

Tiffneau test and/or bronchoscopy

Question 7

What drugs are used to treat asthma and how do they work ?

Answer 7

Beta agonists - salbutamol
Increase cAMP in smooth muscle cells
This inhibits MLCK so prevents muscle contraction
Causing bronchodilation

Question 8

What are common side effect if beta agonists taken in excessive amount ?

Answer 8

Tachycardia
Muscle tremor
Hypokalemia

Question 9

Examples of long lasting beta agonists …

Answer 9

Salmetrol and isoproterenol

Long term prevention of attacks

Question 10

What do muscarinic receptor antagonists do ?

Answer 10

Bronchodilation
Bind to muscarinic receptors in airway smooth muscle preventing acetylcholine binding
Also decrease mucus secretions
Particularly good against irritant induced attacks

Question 11

Examples of muscarinic antagonists..

Answer 11

Short acting: atropine, ipratropium bromide and oxitropium bromide
Longer acting: tiotropium bromide

Question 12

When does max bronchodilation of muscarinic antagonists occur and how long do their effects last ?

Answer 12

Max effects after 30 mins
Short- 5 hours
Long- 15 hours

Question 13

What are xanthines ?

Answer 13

Caffeine and theobromine
They inhibit phosphdiesterase enzymes in airway smooth muscle leading to an increase in cAMP increasing relaxation
Main clinical one: theophylline

Question 14

What are the problems with using xanthines as bronchodilators and what are the adverse effects ?

Answer 14

Narrow therapeutic use

Nausea, cardiac arrhythmias and convulsions and drug interactions

Question 15

Why are anti inflammatory drugs used in asthma ?

Answer 15

Prevent subsequent inflammation

Question 16

What is an example of an AID used in asthma ?

Answer 16

Glucocorticosteriod - inhibits inflammatory cell infiltration and reduces oedema
- beclometasome and budesonide

Question 17

What are the symptoms of COPD?

Answer 17

Excessive sputum production, chronic cough and breathlessness

Question 18

What does chronic bronchitis cause ?

Answer 18

Alveolar hypoventilation
Hypercapnia
Hypoxia

Question 19

What is associated with emphysema ?

Answer 19

Destructive loss of alveolar structure

Chronic impairment of gas exchange

Question 20

What are the treatments for chronic bronchitis ?

Answer 20

Bronchodilators
Mucokinetic drugs - reduce viscosity of mucus - N-acetylsysteine and ambroxol break disulphide bonds
Antibiotics - combat any bacterial infections

Question 21

What is pulmonary oedema ?

Answer 21

Abnormal build up of fluid within alveolar space - cough and impaired gas exchange

Question 22

What are the treatments for pulmonary oedema ?

Answer 22

Try to reduce blood volume to improve cardiac function
Diuretics (furosemide)- increase urinary loss by inhibiting reabsorption at kidney
Cardiac glycosides(digoxin) -
Phosphdiesterase inhibitors and beta 1 agonist

Question 23

What is cystic fibrosis ?

Answer 23

Inherited disease
Primary defect is a mutation I specific proteins essential for chloride efflux
Causes thick viscous secretions in ducted organs
Causes poor ventilation and subsequent bacteial infections

Question 24

What are the aims for the drugs used to treat cystic fibrosis ?

Answer 24

Thining the secretions

Combating opportunistic infections

Question 25

What drugs are used to treat cystic fibrosis ?

Answer 25

Muscarinic antagonists - reduce mucus secretions
Expectorants( glyceryl guaiacolate) - increases fluidity of secretions increasing productivity of coughing
Much lyric agents ( N-actylcycsteine) - decrease viscosity
Antibiotics

Question 26

What happens when you overdose on opioids ?

Answer 26

Centrally mediated depression of respiration
Activated a micro receptor
Inhibits adenylage Cyclase which decrease cAMP
Causes decreased neuronal excitability
Depressing ventilation

Question 27

How is opioid overdose treated ?

Answer 27

Naloxome- opioid receptor antagonist - removes pain relief though
Activate serotonin 4a receptor to increase adenylate Cyclase - mosapride