Therapy

Give a beta-agonist ^a (e.g. salbutamol 2.5 to 5 mg) and an anticholinergic ^a (e.g. ipratropium 500 µg) 
regularly ^a (and continuously if possible ^a )
via an inhaler and holding chamber or via a nebuliser ^a using air or oxygen   ^d   

Give steroids ^a immediately  ^a  in doses of equivalent to 40 mg prednisolone daily. ^a
iv, im or by mouth. ^a  

If patients are not improving, inform your critical care unit and consider using the following

• magnesium sulphate ^a  
  (1.0 to 1.2 g intravenously over 30 minutes) 
• iv beta-2 agonists  ^d 
• aminophylline iv  ^d 
  (e.g. a loading dose of 5.6 mg/kg over 20 min (not if patient has taken theophyllines within the last 24 hours), followed by continuous infusion 0.9 mg/kg per hour.) 
• epinephrine subcutaneously  (0.3 ml 1:1000) ^a
• anaesthetic drugs ^a

• worsening peak flows
• worsening hypoxia or hypercapnia
• exhaustion or confusion
• coma or respiratory arrest

• PEFR > 300 l/min and >60% predicted and improving ^c
• they are symptom-free ^d

Give steroids and advice (see prevention)

There is no clear benefit from 

• heliox (helium/oxygen) 
• antibiotics ^d