Edited by Richard J. Frances and Sheldon I. Miller.
Most codeine is converted from morphine rather than directly derived from opium.
Chemically distinct but act in similar ways. Abrupt withdrawal most often followed by relapse. Gradual withdrawal recommended There are several pharmacological options for withdrawal which can facilitate slow withdrawal through substitution of drug and offer physiological support in withdrawal. Craving for the drug. Mild to moderate sleep disturbance.