The authors have previously described a technique whereby individual
lithium dosage requirements can be predicted from 24-hour blood samples.
Further experience over a 2-year period has shown the predictions to be
reproducible over time. A micromethod for lithium determination is
described, as are several cases in which aberrant results were found to
indicate inadequate laboratory techniques or patients' failure to take
medication. Because the technique reveals immediately those patients at the
extremes of dosage ranges, toxicity and the need for frequent sampling can