Lithium in serum

The concentration of lithium in the blood serum is normally 0.14-1.4 μmol / l, with the intake of lithium preparations in therapeutic doses of 0.8-1.3 mmol / l. Toxic concentration is more than 2 mmol / l.

Lithium ions are absorbed into the digestive tract. It is excreted in the urine( 95%), feces( 1%) and then( 5%).The concentration of lithium in saliva is much higher than its concentration in the serum. The blood-brain barrier is permeable to lithium, and its concentration in CSF is 40% of that in serum. In the human body, the brain is rich in lithium, kidneys, heart muscle and liver. Lithium specifically accumulates in thyroid cells and causes a man to increase the thyroid gland.

Determination of the concentration of lithium in serum is important in the treatment of lithium preparations, as well as for the diagnosis of lithium poisoning.

In humans, signs of lithium deficiency are not documented.

Currently, lithium carbonate is used in psychiatric practice at doses up to 2.5 g / day( 72 mmol), which increases the concentration of lithium in plasma to 0.5-1.5 mmol / l. It should be borne in mind that in some cases, even at a concentration of 1.6 mmol / l, toxic effects can develop. Therapy with lithium is aimed at normalizing the metabolism of the mediators in the central nervous system. Lithium ions also affect some parts of the endocrine system, in particular the adrenal cortex, as well as the secretion of ADH.In psychiatric practice, the greatest effect is achieved in the prevention of affective disorders.

Rules of blood sampling for research. Investigate the serum of venous blood. During the monitoring, the concentration of lithium is determined initially and before the introduction of the next dose of the drug.

There are cases of professional poisoning with lithium aerosols, which can cause tracheitis, bronchitis, interstitial pneumonia and diffuse pneumosclerosis. The ingestion of lithium preparations on the skin and mucous membranes can cause burns. Symptoms of chronic lithium intoxication are expressed in general weakness, drowsiness, dizziness, loss of appetite, pain when swallowing, tremor.