thanks for posting your query to HCM. As I understand you are suffering from asthmatic complaint . this condition is usually due to some allerens . In this illness respiratory muscle goes in to contraction leads to bronchoconstriction make breathing difficult . Ventolin contain the drug that causes broconchodilatation and relieve breathing difficulty. Monteleucast also prevent bronchoconstriction with a different mechanism . So clinician use these medication as per the requirement of different patient . I dont know your present condition but just suggest you that if you can have symptomatic relief using only Ventolin you can continue with it, as these medication provide symptomatic relief only .These medication do not cure the disease . hope it will help you .wish you a good health .