treatment and monitoring of asthma

Question 1

short acting B2 agonists

Answer 1

eg salbutamol
stimulation of B2-receptors on airway smooth muscle
adverse effects
-fine tremor, nervous tension, headache,tachycardia
-HYPOkalaemia at high doses

Question 2

methylxanthines

Answer 2

eg theophylline 
-inhibits phosphodiesterase
-additive effect when used in conjunction with small does of B2 agonists 
-given orally or by very slow I/v infusion 
-hepatically metabolised 
adverse effects
-nausea,headache,insomia
-toxic effects above 25mg/L

Question 3

antimuscarinics

Answer 3

eg ipratropium
-block muscarinic receptors
-administered by inhalation (maximal effect occurs 30-60 mins after use,duration of action 3-6 hours)
adverse effects
-dry mouth,constipation,diarrhoea,cough ,headache

Question 4

preventers

Answer 4

corticosteroids
leukotriene receptor antagonists
cromones

Question 5

corticosteroids

Answer 5

eg beclometasone
-reduce bronchial inflammatory reactions eg oedema
-metered inhalation
-must be used regularly
fewer systemic effects, but
-hoarse voice,reflex cough, oral candidiasis

Question 6

corticosteroids oral therapy

Answer 6

prednisolone 
-acute attacks
-chronic asthma 
-taken as single dose in morning
hydrocortisone I/v injection in emergency treatment of severe acute asthma

Question 7

leukotriene-receptor antagonists

Answer 7

• block effects of cysteine leukotrienes in airways
• effective in late phase response
• well tolerated

Question 8

cromones

Answer 8

eg sodium cromoglicate
-mechanism of action is unclear
-prophylactic drug-of NO VALUE in acute attacks
-must be withdrawn gradually over 1 week
adverse effects may be prohibitive

Question 9

long acting B2 agonists

Answer 9

eg salmeterol

• for use with regularly inhaled corticosteroid
• role in long-term control of chronic asthma
• NOT typically used for relief of an asthma attack

Question 10

monoclonal antibodies

Answer 10

eg omalizumab

• recombinant humanised monoclonal antibody
• selectively binds to IgE forming a complex