make a formulation the same as Entex LA is 600/120.. Mucinex makes the version that is 120/60 I think and 1200/120, I have no idea in the world why they can't make a 600/120 version for in the US here??? I've emailed them to ask them and they have even called me.. however when they call they ask you 40 questions about how you feel, etc.. I know the difference from not taking 600/120 formulation, my sinuses are not completely drained and the back of my neck is tight and hurts. Soon as I take the 1200/120, my neck tightness is gone, however I am all dopped up from the 1200 mg, which is too much.. doesn't make sense why you just can't get 600/120 here in the US any more...