What is being tested?
This test measures the amount of lithium in the blood. Lithium is a drug that is used to treat bipolar disorder. Bipolar disorder is a mental condition that is characterized by cycles of depression and mania. These cycles may be as short as a few days or weeks or may be months or years long. During a depressive episode, those affected may feel sad, hopeless, worthless, and lose interest in daily activities. They may be fatigued but have trouble sleeping, experience weight loss or gain, have difficulty concentrating, and have thoughts of suicide. During a manic episode, those affected may be euphoric, irritable, have high energy and grandiose ideas, use poor judgment, and participate in risky behaviors. Sometimes affected patients will have mixed episodes with aspects of both mania and depression. Bipolar disorder can affect both adults and children.

Lithium is prescribed to even out the moods of the person with bipolar disorder and is sometimes prescribed for patients with depression who are not responding well to other medications. It may take several weeks to months for lithium to affect a person’s mood. Dosages of the drug are adjusted until a steady concentration in the blood is reached. The actual amount of drug that it will take to reach this steady state will vary from person to person and may be affected by a person’s age, general state of health, and other medications that they are taking. Lithium levels must be maintained within a narrow therapeutic range. Too little and the medication will not be effective; too much and patients will experience symptoms associated with lithium toxicity, such as nausea, vomiting, diarrhea, confusion, and tremors. Extremely high levels can lead to stupor, seizures, and can be fatal.

How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.

Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.