a study to evaluate the sensitivity and specificity of inhaled methacholine in bronchial provocation test

Conditions: Asthma

Summary: a multicenter, open-label study to evaluate the sensitivity and specificity of inhaled methacholine in bronchial provocation test


Eligibility criteria:
inclusion criteria: patients who meet all the following inclusion criteria can be included in this trial: * 1 adults 65 years of age ≥ 18 years of age, male or female; * 2 normal or abnormal pulmonary function test without clinical significance (fev1 ≥ 70% predicted); * 3 voluntary, signed informed consent, good compliance, can cooperate with the trial observation. patients with asthma: * 4 clinical diagnosis of asthma patients; * 5 patients who can stop using prohibited concomitant drugs (β2 adrenoceptor agonists, anticholinergics, oral bronchodilators, antihistamines, leukotriene receptor antagonists) within the specified period before airway allergic examination; healthy subjects: * 6 body mass index (bmi) = weight (kg)/height2 (m2), and body mass index is within the range of 18.5 \~ 27.0 (including the critical value). exclusion criteria: patients with any of the following criteria will not be included in the trial: * 1 patients with a past history of allergy to this type of reagent; * 2 patients with a history of heart disease who are difficult to adapt to bronchial provocation test; * 3 patients who have undergone thoracic or abdominal surgery within 6 months before the trial; * 4 patients who have undergone surgery for intracranial, ophthalmic diseases, ear, nose and throat diseases, and respiratory diseases 6 months before the trial; * 5 complicated pneumothorax and other respiratory diseases or tuberculosis and other infectious diseases; * 6 patients with diseases that may be affected by the use of cholinergic drugs (epilepsy, bradycardia, coronary artery occlusion, vagal tension, thyroid disease, arrhythmia, peptic ulcer, urinary tract disorders, etc.); * 7 patients with a past history of drug dependence or alcohol dependence; * 8 previous severe circulatory system diseases, hepatobiliary system diseases, digestive tract diseases, urinary system diseases, kidney diseases, blood diseases, endocrine system diseases, immune system diseases, malignant tumors, etc.; * 9 patients who are using cholinase inhibitors (treatment of myasthenia gravis); * 10 patients with unexplained urticaria; * 11 pregnant and lactating women; * 12 subjects with dyspnea, wheezing, wheezing on the day of the trial; * 13 patients with myocardial infarction or stroke, combined with hypertension (systolic blood pressure \> 200 mmhg, diastolic blood pressure \> 100 mmhg); * 14 poor cooperation in basic pulmonary function tests, not in line with quality control; * 15 use of drugs that will affect airway systolic function and airway inflammation, thereby affecting airway reactivity and can not be discontinued before the test (bronchodilator drugs, glucocorticoids, anti-allergic drugs and triene receptor antagonists and others); * 16 current smokers, those who quit for less than one year at the time of screening, and those with a smoking history of more than 10 packs/year; * 17 abnormalities in physical examination, laboratory tests, vital signs and test-related tests are clinically significant (based on clinician judgment); * 18 the investigators think that there are any unsuitable for inclusion; patients with asthma: * 1 hospitalized for asthma exacerbation within 12 weeks; * 2 patients with combined respiratory diseases (such as copd, etc.) that may affect the efficacy and safety evaluation of the drug; healthy subjects: * 1 have used any drugs in 2 weeks; * 2 patients, immediate family members suffering from allergic diseases (allergic rhinitis, specific rhinitis, allergic conjunctivitis, chronic urticaria, food allergy, etc.); * 3 patients with upper respiratory tract infection, acute sinusitis and other infection-related symptoms or have received treatment in 6 weeks.