- OralCodeineWeakly agonises all opioid receptors
Up to 10% of the population lack the enzyme required to convert codeine (weak) to morphine (potent) – in these cohorts codeine has nearly no effect
- Mechanism of Action
- Acts on opioid receptors (δ, κ and µ) and nociceptin orphanin FQ (NOF) receptors on neuronal cell membranes within the thalamus, diencephalon, midbrain and medulla, resulting in reduced neurotransmitter release.
- Adverse Effects