Do not eat a heavy meal or exercise for 4 hours before the breathing test.
Do not smoke for 6 hours before the test.
Wear comfortable loose fitting clothing.
Avoidance of certain medications, including antihistamines (for 3 days prior), asthma reliever inhalers (for 6 hours prior), long acting relievers, theophylline and other asthma medication (all for 24 hours prior).
