I don't know about Prescription, but I had a bad experience with Physicians Weight Loss about 25 years ago. After I signed up they gave me a menu plan with the daily calories adding up to 500!!! Even in my 20s I knew this was insane. I told them I would not do it. So they gave me a "modified" plan with 800 calories per day, which in retrospect is still crazy low. I kept my contract with them, which basically meant weighing myself every week on their scale, and ended up devising MY OWN menu plan and losing 45 pounds on it. Waste of money, if you ask me.