By the same token, if a doctor prescribes, say, 50 Vicodin or
hydrocodone (or any Schedule III narcotic) for you
and you cannot afford to buy the whole prescription at once, you CAN buy whatever you can afford, leave the rest at the pharmacy, and go back at another time to pick those up. With Schedule II narcotics, if you cannot afford to purchase the whole prescription at one time, you must forfeit however many you cannot afford to pay for at the time.