Hi,
My 6 year old was on singulair for about 3 weeks. I took him off of it because he was getting nightmares, and was then cranky and sensitive all day long. Switching it to day time did not help either. He used to cough and cough. So although I didnt want him to be on an inhaled steroid, he now takes flovent 2 puffs a day when sick, (colds ect) and 1 puff a day when well. He takes his albuterol only if he has an attack . ( He has only needed the albuterol once this year) We had been at the hospital at least 6 times a year due to his asthma, he only had 1 visit this year since being on the flovent. I hate to have him on it, but it has helped his lungs function much better. We are also in the process of changing his diet (no processed foods, or junk ect) to try to get him well enough to take him off the flovent too.
Good Luck to you! p.s. have you tried a pulmonologist?