ICU Workload

I work in ICU where the work load is not that bad compared working on the ward. The most patients we can have is two and when our patient is ventilated we only have one. But mind you we stay with the patient all the time. Imagine our 12.5 hours shift. 11-11.5 hours of it is with the patient. Sometimes there is nothing to do except watching the patient who doesn't move because they are sedated. Us nurses will just be sitting watching the lying patient. No wonder I am gaining weight. Anybody knows what's the best diet pills that actually work? If you do please tell me.