I live in the U.S., first off.
I was prescribed a narcotic following a minor surgery. I'm not going to say what kind of surgery that was and please don't ask. I'll just go ahead and say that the prescription was for hydrocodone/acetaminophen 5-35. I'm worried about having been prescribed this because I know there's a state-wide electronic system used to monitor all prescriptions—accessible by all doctors, pharmacies, etc. anywhere else in my state—and I know that system is used to flag people for prescription drug abuse. I also know that medications like this are highly frowned upon by the healthcare system itself and even more so by the authorities. I assume it's entirely possible that I look suspicious according to that system now.
I've only taken a three pills so far, out of ten total. If I take the other seven back to the pharmacy to have them destroyed, they'll make a record of that, I would imagine.
What I mean is that I could just stop taking them now but never tell anyone that, and anyone looking at my medical history in the future would see that I picked up ten pills from the pharmacy, and that's all they would see, and so I took the entire script as far as they know; whereas if I take the other seven back, and they make another entry in their records about that, that's in effect like plus ten and then minus seven, and that way I would theoretically have three pills counted against my medical history instead of ten; right?
I could be way overanalyzing this, but frankly, I'm already terrified to take another one anyway. I honestly don't like how they make me feel, which is good, but it would be just my luck that I'd take one more pill and start liking it immediately. I know what happens to people who end up liking this stuff, and how easy it is to end up liking it; I've seen it. It's also that I'm still relatively young, and my health's already bad enough at this point as it is, that I already know they'll eventually put me in the ground with at least one major surgery, and I don't want to have to get through that with ibuprofen because I've already blown it.
You're over analyzing.
The system is (supposedly) to track narcotics to prevent overprescribing. Your one-off script because of one surgery isn't a concern.
Take what you need. Don't think just because today you feel OK you don't need the refill - pain can be sneaky, and come back with a vengeance tomorrow. What the surgeon prescribed is based on experience with prior surgeries - there's a bell curve of post-op pain level and time, that's used to guide prescribing.
For example, after one surgery I felt fine and had already been given a strong pain med injection, and figured I'd be fine for a few hours. When my nurse realized my pain med prescription hadn't been filled yet, she rushed off to get another shot for me, knowing that I'd shortly be in major pain. She'd seen enough of that type surgery to know how it works for most people. I thought I had plenty of time to get it filled.
The focus of the tracking system (ostensibly) is to expose patterns of abuse...which is (supposedly) more likely from long-term use/prescriptions (months/years) - such as with chronic pain sufferers. It's more concerned with docs over-prescribing, since they instruct the pharmacy what to give you - you can't just walk in and say "gimme 30 vicodin".