Thanks for writing lily. First, let me say that any treatment regimen should be developed in conjunction with your doctor. My research indicates that there is no particular reason Symbicort and ventolin can not be used together. If you find that you regularly need to use the rescue inhaler, it may be an indicator that your asthma is not in good control and your treatment plan may need to be adjusted. Hopefully some others can chime in with their experiences with these medications. Wishing you the best. Richard (Asthma.net Team)