What dose FAQ mean?

Buprenorphine is a thebaine derivative, and its analgesic effect is due to partial agonist activity at μ-opioid receptors, i.e., when the molecule binds to a receptor, it is only partially activated in contrast to an full agonist such as morphine. Buprenorphine also has very high binding affinity for the μ receptor such that opioid receptor antagonists (e.g. naloxone) only partially reverse its effects. These two properties must be carefully considered by the practitioner, as an overdose cannot be easily reversed (although overdose is unlikely in addicts or people with tolerance to opioids who use the drug sublignually as meant in the case of Subutex/Suboxone, especially if there are no benzodiazepines involved), and use in persons physically dependent on full-agonist opioids may trigger opioid withdrawal that also cannot be easily reversed and can last over 24 hours, as the drug's mean half-life is 37 hours. For this reason, patients switching to buprenorphine are required to abstain from the previous opioid for at least several half-lives of the given substance.