Lithium control for psychiatrists
Measuring lithium levels
This test measures the level of lithium in the blood. (Serum)
The main reasons to test your blood lithium levels are:
1. Treatment with lithium (in bipolar disorder and depression).
- Monitor optimal dosage: Lithium has a narrow therapeutic window - too low it does not work, too high it can be toxic.
- Prevention of toxicity: High levels of lithium can lead to poisoning with symptoms such as nausea, tremors, drowsiness and, in severe cases, kidney problems or neurological damage.
- Monitoring adherence: Measuring lithium levels can help determine whether a person is taking the medication correctly.
2. Monitoring renal function and lithium excretion.
- Lithium is excreted by the kidneys, so a test can detect kidney problems that interfere with lithium balance.
- With loss of renal function, lithium may accumulate, increasing the risk of toxicity.
3. Unexplained complaints or symptoms
- Symptoms such as fatigue, tremors, difficulty concentrating or mood swings may indicate a lithium imbalance.
- Both a deficiency (insufficient activity) and an excess (toxic effects) can cause health problems.
4. Medication interactions and lifestyle factors.
- Some medications and habits (such as fluid intake, salt intake or diuretics) can affect lithium excretion.
Regular testing can verify whether these factors are upsetting the lithium balance.
Lithium is an effective drug for treating patients with bipolar (manic-depressive) disorder. However, it is a drug with many, potentially serious side effects and a narrow therapeutic breadth. Regular monitoring of lithium concentration and regular monitoring for side effects should therefore take place.
Lithium use in most cases is supervised by a psychiatrist with extensive experience in the effects and side effects of lithium. However, in long-term use by psychiatrically stable patients, care is sometimes left to the general practitioner. Non-psychiatrists should also remain alert to the side effects of lithium.
Therapy monitoring and assessment in lithium therapy,
Clarification of toxic lithium effects in muscle twitching, balance and movement disorders, drowsiness, convulsions, dehydration.
Therapeutic range: 0.5 - 1.2 mmol / l
- Toxic side effects: 1,5 mmol/l
- Dehydration and comatose state: 3.0 mmol/L
- Potentially lethal: 4.0 mmol/l
Lithium is excreted by the kidneys (increased with high sodium and water intake).
elimination half-life: approximately 14-33 hours.
Toxic side effects of 1.5 mmol/l: Muscle twitching, ataxia, drowsiness, convulsions, dehydration, coma
Bud decline about 12 hours after last lithium intake.
The result should be discussed with your psychiatrist. Blood value testing does not provide support in this regard.
When taking lithium, it is wise to monitor kidney function, electrolytes, thyroid levels and blood glucose in addition to lithium levels. This helps to prevent side effects and adjust the medication as optimally as possible.
If you test your lithium level, the following related tests may also be useful to get a broader picture of your health and electrolyte balance:
1. Kidney function study
- Kreatinine & eGFR - Since lithium is excreted through the kidneys, it is important to check that your kidneys are functioning properly.
- Urinalysis - To detect any kidney problems or fluid imbalances.
2. Electrolyte balance
- Sodium, Potassium, Magnesium and Calcium - These minerals affect lithium excretion and can cause fluctuations in lithium levels.
3. Thyroid function
- TSH, FT4 & FT3 - Lithium can affect thyroid function and sometimes lead to hypothyroidism. Regular monitoring is recommended.
4. Blood Glucose and Insulin Resistance.
- HOMA-IR, Fasting Glucose, Insulin & HbA1c - Lithium use can affect metabolism and insulin resistance, especially in people at increased risk for type 2 diabetes.
5. Liver function
- ALAT, ASAT, Gamma-GT, Bilirubin - To monitor liver health, as lithium can sometimes affect liver function.
6. Vitamins and Minerals
- Vitamin D, B12 & Folic Acid - Lithium use can affect the absorption of certain vitamins, leading to deficiencies and fatigue symptoms.
