What is Li?
Lithium (Li+) is an element which is used as an antipsychotic drug. It treats bipolar disorder and mania, as well as some other psychological diseases like depression as an augmenting agent. The Lithium Test is performed to measure the concentration of lithium in blood.
Why is Li done?
· To establish a therapeutic dosage for lithium
· To monitor blood concentration at regular intervals to help maintain the therapeutic concentration
· To check for lithium toxicity upon the appearance of symptoms
What does Li Measure?
Lithium is an alkali metal which occurs in trace amounts in the human body mainly obtained from dietary sources. Lithium compounds are used as antipsychotic drugs for the treatment of Bipolar disorder. Bipolar disease is a psychological condition where the patient goes through alternating periods of severe depression and mania. It is thus associated with sudden and unpredictable mood swings. Lithium is prescribed as a mood stabilizer to treat these sudden mood swings. It is also used as an augmenting agent for patients being treated for depression but not responding to standard medications. Lithium may also be prescribed for other psychological diseases as an augmenting agent.
Lithium is a drug which acts relatively slowly and may take several weeks to be effective in treatment. Hence, its concentration in blood needs to be maintained within a steady therapeutic range for it to be effective as a drug. Lower than the therapeutic range concentrations make it ineffective as a medicine, while higher than the therapeutic range concentration causes lithium toxicity. The blood level of lithium is thus monitored at regular intervals to help maintain it within the effective therapeutic range.
Interpreting Li results
Therapeutic range: 0.6 to 1.2 mmol/L
The standard therapeutic range of lithium concentration may vary from person to person and is usually established at the beginning of the treatment.
Lower than the therapeutic range lithium concentration makes the drug ineffective in treatment.
Higher than the therapeutic range lithium concentration induces symptoms associated with lithium toxicity.