I'm overweight. I'd love to lose 30lb. I exercise quite a bit (as much as life allows) and watch my diet. However, my weight is biased towards drifting up.
I tried a version of this (eatable, not injectable) for 6 months before giving up. Here is why.
My eating is not and has never been because of hunger. It is 100% triggered by stress. I eat for comfort when things pile up. Not an uncommon experience among fat people.
The drug did suppress my appetite, to the point where I no longer felt any sort of hunger whatsoever. If anything, due to the secondary symptoms, I did not feel like eating anything for most of the day.
However, it did nothing to control my stress eating! During the evenings, after a tough day at work or dealing with the kids, I'd vacuum up everything in the fridge even though I felt no hunger and in fact was difficult to eat! The seratonin hit due to food going into the belly overcame all these inhibitors. I lost no weight during the 6 months I was on this thing.
Other symptoms:
1) Constant, low-grade nausea
2) Feeling of tiredness and mild depression
3) Constipation
For those whom these drug helps: you have my best wishes and envy.