also, if someone offered you a medication that worked as well as Imitrex, you would probably use it when you were in pain as a substitute
for Imitrex... which all shows that
Imitrex is in no way addictive. As
for physical dependency... well, I have heard of the triptan Maxalt causing rebound headaches, which could be considered a type of physical dependency maybe... but, out of all of the triptans, the ONLY triptan that has shown this is Maxalt, not Imitrex.