How long after 3 day course of Afrin can I use again?

I understand that when you use Afrin nasal spray, that you are only suppose to use it for 3 days in a row to prevent rebound or addiction. 

My question is - After doing a 3 day course of Afrin (according to directions), how many days in-between should you wait before you can do another 3 day course?

Thank You,

Dawn