Asthma Patients with asthma have higher<unk>  levels than other people. Their levels also rise together with other clinical and laboratory parameters of asthma (for example, the amount of eosinophils in their sputum). In conditions that trigger inflammation such as upper respiratory tract infections or the inhalation of allergens or plicatic acid,<unk>  levels rise. The<unk>  levels also tend to vary according to the results of lung function test results such as the degree of bronchial hyperresponsiveness. Furthermore, drugs used to treat asthma (such as inhaled glucocorticoids or leukotriene receptor antagonists) also reduce<unk>  levels. Clinical trials have looked at whether tailoring asthma therapy based on<unk>  values is better than conventional care, in which therapy is gauged by symptoms and the results of lung function tests. To date, the results in both adults and children have been modest and this technique can not be universally recommended. It has also been noted that factors other than inflammation can increase<unk>  levels, for example airway acidity. The fraction of<unk>  has been found to be a better test to identify asthmatics than basic lung function testing (for airway obstruction). Its specificity is comparable to bronchial challenge testing, although less sensitive. This means that a positive<unk>  test might be useful to rule in a diagnosis of asthma; however, a negative test might not be as useful to rule it out.
Exhaled nitric oxide
Peak expiratory flow
FEV1/FVC ratio
Integrated pulmonary index
Fraction of inspired oxygen
Peak inspiratory pressure
Mandatory minute ventilation
Diffusing capacity for carbon monoxide