Partial and Mixed Opioid Mu Receptor Agonists and Antagonists

buprenorphine

- partial

- has a ceiling effect (aka max efficacy, can't keep giving)

- 30-50x more potent than morphine

- slower onset (~45min) and longer duration (up to 8hrs)

- less apparent side effects

- used IV, IM, SC, TM, IN, TD

butorphanol

- mixed, synthetic K agonist and m antagonist

- less analgesia than pure m agonists

- visceral pain

- antitussive effects

- anxiolytic effects

opioid potency

1. morphine

2. methadone

3. butorphanol

4. hydromorphone

5. oxymorphone

6. buprenorphine

7. fentanyl

8. remifentanil

naloxone

- full mu receptor antagonist

- competitive

- reverse analgesia

- rapid onset and short duration

tramadol

- MOA: weak opioid mu agonist

- inhibits serotonin and NE uptake (CAUTION IF CONCURRENT SSRI)

- serotonin syndrome

hydrocodone

- no refills, 1mo supply only

- orally as antitussive

opioid precautions

- dose-dependent CV/resp depression

caution:

- advanced or severe cardiac disease

- existing ileus

- acute renal injury

- history