Lithium level

Clinical definition of the Lithium level test
Lithium test measures the amount of lithium in the blood in order to determine whether drug concentrations are in the therapeutic range. It is prescribed in the treatment of bipolar disorder. Bipolar disorder is a mental condition that is characterized by alternating periods of depression and mania. Lithium serves as a mood stabilizing drug. Upon ingestion lithium interacts with a number of neurotransmitters and receptors, decreasing norepinephrine release and increasing serotonin synthesis. Lithium levels are monitored as blood levels must be maintained within a narrow therapeutic range. Excess of lithium leads to lithium toxicity and develops symptoms such as nausea, vomiting, confusion, tremors and with insufficient amounts the medications might not be effective.

Why is the Lithium level test done?
Lithium test is carried out to determine lithium levels in the blood. It is used to treat mania (high mood with over reactivity, racing thoughts and agitation), to help prevent the recurrence of severe mood swings after an acute episode of bipolar illness, and to boost the effect of antidepressants.

What are the common signs/symptoms when the Lithium level test is done?

  • Depression
  • Racing thoughts
  • Agitation
  • Severe mood swings, mood is excessively high on some occasions and very low on others
  • Irritable
  • High energy and grandiose ideas
  • Poor judgment
  • Risky behavior
  • Trouble sleeping
  • Experience weight loss or gain
  • Difficulty concentrating
  • Thoughts of suicide
  • Lose interest in daily activities
  • Feeling of sadness and hopelessness

Who should do the Lithium level (Target population)?
Persons showing the above signs & symptoms.

What should I do before the Lithium level, serum by ISE test?

Specimen type

Specimen collection procedure

Preparatory instructions before the test *

Serum (Blood Sample)


Collection of blood from a vein, usually from the arm.

No Fasting Required.

No other special preparations required.

*Subjects suffering from any illness or on oral or injectable medications are advised to consult their physician prior to requesting any tests or procedures.

How do I interpret my Lithium level, serum by ISE test results?

Reference Range* (Mmol/L)


0.6 to 1.2

Therapeutic range

Above 1.5

Potentially Toxic

Above 2.0

Severely Toxic

‘*A Reference range is a set of values which helps the healthcare professional to interpret a medical test. It may vary with age, gender, and other factors. Reference ranges may also vary between labs, in value & units depending on instruments used and method of establishment of reference ranges’

Diseases/conditions related to the Lithium level test

  • Bipolar Disorder
  • Major depressive disorder (MDD)
  • Mania
  • Cycloid Psychosis
  • Depression

Other tests related to the Lithium level

  • Therapeutic drug monitoring
  • Emergency and Overdose Drug Testing
  • BUN
  • Creatinine
  • TSH
  • Thyroid antibodies