Physiology of Cough in Asthma: Comparison of Sensory-Mechanical Responses to Mannitol and Methacholine Challenge Tests

Exclusion Criteria

• •1. An exacerbation necessitating any alteration in medication, emergency department visit or hospitalizations within the previous 4 weeks;
• •2. Inability to perform acceptable quality spirometry;
• •3. Medical contraindications to methacholine challenge testing 35, including:
• •1. Severe airflow limitation (FEV1 \<50% predicted or \<1.0 L);
• •2. Heart attack or stroke in last 3 months;
• •3. Uncontrolled hypertension, systolic BP \> 200 or diastolic BP \> 100;
• •4. Known aortic aneurysm;
• •5. Moderate airflow limitation \< 60% predicted or \<1.5 L);
• •6. Inability to perform acceptable quality spirometry;
• •7. Current use of cholinesterase inhibitor medication (for myasthenia gravis); and
• •8. Pregnant or nursing mothers.
• •4. Smoking history in excess of 10 pack years;
• •5. Medical contraindications to mannitol challenge testing, including:
• •1. Aortic or cerebral aneurysm;
• •2. Uncontrolled hypertension; and
• •3. Myocardial infarction or a cerebral vascular accident in the previous six months).
• •6. Women who are pregnant or breastfeeding because the effects of a possible hyperresponsiveness reaction to mannitol in mothers and/or fetuses are unknown and many compounds are excreted in human milk therefore caution should be taken.