see also:

• pain, analgesia and analgesics
• opiates and opioids
• tramadol
• Opioid dose converter app

• synthetic opiate-like analgesic similar to tramadol invented in the late 1980's and approved by TGA in Australia in 2010 as an S8 controlled drug
• as with tramadol it has a dual mode of action as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor (NRI)
• analgesic efficacy comparable to that of oxycodone despite an alleged lower incidence of side effects
• 100mg immediate release tapentadol appears to have similar analgesia to 15mg oxycodone but with less N/V although more somnolence
• 100-250mg SR tapentadol bd appears to equate to 20-50mg SR oxycodone bd for analgesia

• only 1/3rd of dose makes it past 1st pass hepatic metabolism
• onset of action after oral administration is around 30min
• duration of action of immediate release oral form is 4-6hrs
• cleared mainly via hepatic metabolism
• those who are rapid or ultra rapid metabolizers for the CYP2C9, CYP2C19, and CYP2D6 enzymes may not respond adequately to tapentadol therapy

• epilepsy or in those prone to seizures as lowers seizure threshold
• raises intracranial pressure so avoid in head injuries, patients with brain tumours, etc
• patients at risk of respiratory depression eg. COPD, OSA, other resp. depressant medications
• patients with low BP as may cause further lowering of BP
• biliary disease or pancreatitis as may cause spasms of the sphincter of Oddi
• liver disease as risk of reduced clearance and toxicity
• patients on monoamine oxidase inhibitors (MAOIs) as risk of adrenergic storm
• patients taking anti-muscarinic anticholinergic agents as risk of urinary retention

• immediate release form:
  • 50-100mg 4-6hrly o
• slow release form:
  • 100mg bd o

• Palexia