CHAPTER 3 – RESPIRATORY SYSTEM
3.1 BRONCHODILATORS
ASTHMA
o Drugs used in management of asthma
Beta2 agonists, antimuscarnic bhroncodilators, theophylline, corticosteroids, cromoglicate
and nedrocromil and leukotriene receptor antagonists
o These drugs can be given by inhalation, orally and parenterally
o During pregnancy, it is important that asthma is well controlled, but to minimise harm to the foetus
drugs should be given by inhalation
o Asthma treatment is done in a step wise manner according to the BTS guidelines
COPD
o Symptoms can be alleviated by an inhaled short acting beta 2 agonist or a short acting antimuscarnic
bronchodilator
o In more SEVERE COPD: the regular use of a short acting antimuscarnic bronchodilator, and if this
does not control the symptoms, then a long acting beta 2 agonist or long acting antimuscarnic
bronchodilator should be added
o If patient becomes unable to use an inhaler, aminophylline or theophylline should be used
o Mucolytic can be used for a chronic productive cough
o During exacerbation:
Bhronchodilator therapy through a nebuliser
IV aminophylline
Short course of oral corticosteroids (e.g. prednisolone 30mg OD for 7-14 days)
CROUP
o Bacterial/viral infection causing inflammation/narrowing of airways
o Mildly self limiting but tx with a single dose of corticosteroids may be of benefit
3.1.1 Adrenoceptor Agonists
3.1.1.1 Selective ß2 agonists
Short acting ß2 agonists (RELIEVERS) – Effects last 3-5 hours
o Salbutamol
o Terbutaline
Long acting ß2 agonists – Effects last 12 hours
o Formoterol
o Salmeterol
CSM: Hypokalemia may result from ß2 agonist therapy
3.1.2 Antimuscarinic Bronchodilators
Ipratropium
o ST relief in chronic asthma
o ß2 act faster and are more preferred
o ST relief in COPD
o Maximal effect 30-60 minutes after use
o Duration of action: 3-6 hours, treatment can usually be maintained with tx TDs
Tiotropium
o Long acting
o Effective in management of COPD, not suitable for relief of acute bronchospasm
3.1 BRONCHODILATORS
ASTHMA
o Drugs used in management of asthma
Beta2 agonists, antimuscarnic bhroncodilators, theophylline, corticosteroids, cromoglicate
and nedrocromil and leukotriene receptor antagonists
o These drugs can be given by inhalation, orally and parenterally
o During pregnancy, it is important that asthma is well controlled, but to minimise harm to the foetus
drugs should be given by inhalation
o Asthma treatment is done in a step wise manner according to the BTS guidelines
COPD
o Symptoms can be alleviated by an inhaled short acting beta 2 agonist or a short acting antimuscarnic
bronchodilator
o In more SEVERE COPD: the regular use of a short acting antimuscarnic bronchodilator, and if this
does not control the symptoms, then a long acting beta 2 agonist or long acting antimuscarnic
bronchodilator should be added
o If patient becomes unable to use an inhaler, aminophylline or theophylline should be used
o Mucolytic can be used for a chronic productive cough
o During exacerbation:
Bhronchodilator therapy through a nebuliser
IV aminophylline
Short course of oral corticosteroids (e.g. prednisolone 30mg OD for 7-14 days)
CROUP
o Bacterial/viral infection causing inflammation/narrowing of airways
o Mildly self limiting but tx with a single dose of corticosteroids may be of benefit
3.1.1 Adrenoceptor Agonists
3.1.1.1 Selective ß2 agonists
Short acting ß2 agonists (RELIEVERS) – Effects last 3-5 hours
o Salbutamol
o Terbutaline
Long acting ß2 agonists – Effects last 12 hours
o Formoterol
o Salmeterol
CSM: Hypokalemia may result from ß2 agonist therapy
3.1.2 Antimuscarinic Bronchodilators
Ipratropium
o ST relief in chronic asthma
o ß2 act faster and are more preferred
o ST relief in COPD
o Maximal effect 30-60 minutes after use
o Duration of action: 3-6 hours, treatment can usually be maintained with tx TDs
Tiotropium
o Long acting
o Effective in management of COPD, not suitable for relief of acute bronchospasm
