Hello, The baby has a wheezing illness that may be triggered by a number of causes. In this age group, the occurrence of particular viruses such as RSV are associated with wheezing. Viruses are not affected by antibiotics. The nebulized treatments and steroids treat wheezing and associated inflammation. Reflux of stomach fluid and contents into the lung may cause wheezing as well. If there is poor weight gain, I would suggest a screening test for Cystic Fibrosis a genetic disease that can present as wheezing and poor weight gain. My practice PRMG is available for telephone consults. If you would like to discuss your child s care, a summary of the problem, her records and medication list, and a copy of your insurance card can be faxed to: 858 259 9689, and I can call you back with a number provided. Thank you for your question.