| Mechanism | Mimics endogenous opioids, acting on opioid receptors |
| Typical Dose | 10mg every 4 hours - adjusted according to response |
| Indications | * Severe pain * Acute pulmonary oedema due to HF * Intractable cough |
| Contra-indications | * Severe respiratory disease (depressant) * ↑ ICP and head injury (changes pupil response for neuro obs) * Undiagnosed Acute Abdomen * Acute alcohol intoxication (depressant) * Hepatic failure |
| Side-effects | N&V, drowsiness, constipation, dry mouth, respiratory Depression Dependance |
| Interactions | Hypnotics: enhances sedative effect |
| Elimination | |
| Additional Notes | Effects can be reversed with naloxone. Tolerance begins after 2 weeks of continuous use - after which dose should be increased |