Lithium: Pharmacological aspect

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ithium is not only the element of the periodic table or a metal, but also has medicinal properties.

Lithium is 3rd element of the periodic table with the mass of 6.941. It has 1 electron in the outer most shell of its structure.

Lithium is a mood stabilizer with an anti-suicidal effect. Lithium is the drug of choice for bipolar disorders as it is a mood stabilizer.


Clinical studies have shown tat lithium reduces the incidence of suicide in Bipolar 1 disorder patients six-seven folds.

FDA approved indications of lithium –

1.    Treatment of acute mania

2.    Prophylaxis of bipolar mood disorders.

Very rapidly absorbed from GIT, peak serum levels occur between 30 minutes to 3 hours. It is completely absorbed from GIT in 8 hours.

Maximum levels occur in thyroid (3-5 times serum level), saliva (2 times), milk (0.3 – 1.0 times) and CSF (0.4 times). Steady state levels are achieved in 7 days.

Lithium is almost completely excreted by the kidney and has relatively no metabolism. As proximal reabsorption is achieved by the use of sodium ions in the kidney, sodium levels are depleted this results in retention of water thus further facilitating the absorption of lithium in blood.

Serum concentration of lithium indicates –

1.    Therapeutic level = 0.8-1.2 mEq/L

2.    Prophylactic level = 0.6-1.2 mEq/L

3.    Toxic levels = >2.0 mEq/L

Side effects of lithium –

1.    Neurological = Tremors, seizures, coma, delirium, drowsiness, increased deep tendon reflexes.

2.    Renal = nephrotic syndrome, polyuria (increased urination).

3.    Cardiovascular = T wave depression

4.    Endocrine = Weight gain, goitre, abnormal thyroid function.

5.    GIT = Nausea, vomiting, diarrhoea, metallic tase, abdominal pain.

6.    Dermatological = Worsening of psoriasis, acneiform eruptions.

7.    Pregnancy and lactation = Secreted in milk that causes toxicity to the baby while breastfeeding, Ebsteins anomaly.

8.    Leucocyte count is increased (increased WBC).

Lithium is to be stopped 2 days prior to surgery.

Lithium is not given in these conditions –

1.    Presence of cardiac, thyroid, renal or neurological dysfunction.

2.    1st trimester of pregnancy

3.    Concomitant administration of thiazides diuretics, tetracyclines or anaesthetics.

4.    Presence of blood dyscrasia (dyscrasia means mixing of blood with bile or other substance).


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