Mean serum concentration–time curves of the R- and S-stereoisomers of ketamine and norketamine, dehydronorketamine, and 2,6-hydroxynorketamine after intravenous infusion of 5 mg ketamine hydrochloride solution within 30 min (bold red lines) and oral administration of 10 mg (yellow lines), 20 mg (green lines), 40 mg (bold blue lines), and 80 mg (black lines) prolonged-release ketamine tablets in 15 healthy subjects. SDs are given for the intravenous infusion and 80 mg tablets only.