Like this post?
The Suboxone preparation contains the μ-opioid receptor antagonist naloxone which is intended only to prevent abuse of the buprenorphine, not, as is commonly misunderstood, to block the effects of other opiates. Buprenorphine itself binds more strongly to receptors in the brain than do other opioids, making it more difficult to become intoxicated due to other opioids when buprenorphine is in the system, regardless of the presence of the naloxone.
If enough buprenorphine is in the system, however, it has the same effect as naloxone in completely or nearly completely blocking or reversing opiate effects from another opioid.
All from Wikipedia. Doesn't say how long it stays in the system but I'd assume it's going to stop your pills from working for at least a few days.