This study is designed to compare the effects of hypertonic saline 5 and 7% in the treatment of bronchiolitis in infants aged 2 months to 2 years. The study population will be 90 children aged 2 to 24 months with viral bronchiolitis admitted to Ardabil Buali hospital. Patients will be entered in this study with block randomization method of sampling and they will be divided into three groups of 30 people. This will be a double blind study namely both the subjects participating and the researchers will be unaware of medication type. Inclusion criteria are first or second episode of respiratory distress with wheezing and diagnosis of viral bronchiolitis based on the standard definition of bronchiolitis. Exclusion criteria are history of previous wheezing attacks more than 2 times, heart and lung disease, immunodeficiency, Down syndrome, metabolic diseases, use of mechanical ventilation, positive family history of asthma, and Patients who are critically ill. The first group will be treated with 0.15 mg/kg adrenaline along with hypertonic saline 5%, The second group will be treated with 0.15 mg/kg adrenaline along with hypertonic saline 7%, and the third group as the control group will be treated with the standard treatment, namely, 0.15 mg/kg adrenaline along with normal saline 0.9%. For all patients in the three groups, clinical symptoms (cough, wheezing, respiratory rate, heart rate, fever, crackles, oxygen saturation) and length of hospital stays will be recorded.