In clinical laboratories, lithium can be determined by flame emission spectroscopy (FES) or atom absorption spectroscopy (AAS). The latter of these is more precise and represents the reference assay method. However, FES is cost-efficient and the method used in most laboratories.
Lithium ion selective electrodes (Li-ISE) have recently become affordable and allow for the rapid determination of serum lithium levels while the patient is present. This results in better therapy compliance, as the patient experiences the treatment process in a more immediate and visual manner. The rapid feedback offers both the patient and the physician a number of advantages.