True statement regarding methadone are all except:
Ref: Goodman and Gilman 12th/506-507 Methadone *The onset of analgesia occurs 10-20 minutes after parenteral administration of methadone and 30-60 minutes after oral administration. *It is well absorbed from the GI tract and can be detected in plasma within 30 minutes of oral ingestion. *Primary uses are relief of chronic pain and in main tenance therapy of opioid addiction.
It is a long acting mue-receptor agonist
It is rapidly absorbed from the gastrointestinal tract and is detected in plasma 30minutes after oral administrations
The primary use of methadone is relief of chronic pain
The onset of analgesia is 30-60 minutes after parenteral administration and 1-2 hours after oral administration
Central Nervous system