Table 2.

Morphine area under the curve (AUC) and maximum plasma concentrations (Cmax) in poor, extensive and ultra‐rapid metabolisers following a single oral dose of 30 mg codeine (Kirchheiner et al., 2007)

Metaboliser type	AUC median (range)	Cmax median (range)
Poor	0.5 (0.5–2.8)	0.05 (0.03–0.07)
Extensive	11 (5–17)	2.1 (0.6–4.3)
Ultra‐rapid	16 (10–24)	2.6 (1.5–4.6)