If you go off them, you no longer suppress appetite and gain the weight back.
Right, it should follow the experience from diet modification and so forth. For the majority of people who would be using the drug it is likely to be a long term proposition because the weight will come back.
you are probably correct about duration/chronicity of these meds; my view is skewed by what I do - I have seen a lof of patients lately who have been on these drugs for wt loss and stopped bc they are trying to conceive. But clinically I have seen a lot of shorter term users, again through my unique lens