Also known as
- Lithium compounds
- Lithium salts
Lithium is mood stabilising drug used most commonly prophylatically in
bipolar disorder but also as an adjunct in refractory depression. It has
a very narrow therapeutic range (0.4-1.0 mmol/L) and a long plasma
half-life being excreted primarily by the kidneys.
Common indications
- Used in the treatment of manic depressive psychosis and for prophylaxis in bipolar disorder.
Mechanisms of action
not fully understood, two theories:
- interferes with inositol triphosphate formation
- interferes with cAMP formation
Important adverse effects
- nausea/vomiting, diarrhoea
- fine tremor
- nephrotoxicity: polyuria, secondary to nephrogenic diabetes insipidus
- thyroid enlargement, may lead to hypothyroidism
- ECG: T wave flattening/inversion
- weight gain
- idiopathic intracranial hypertension
Warnings
Important interactions
Monitoring
- Range = 0.4 - 1.0 mmol/l
- Take 12 hrs post-dose
- Lithium testing
- inadequate monitoring of patients taking lithium is common - NICE and the National Patient Safety Agency (NPSA) have issued guidance to try and address this. As a result it is often an exam hot topic
- after starting lithium levels should be performed weekly and after each dose change until concentrations are stable
- once established, lithium blood level should 'normally' be checked every 3 months. Levels should be taken 12 hours post-dose
- thyroid and renal function should be checked every 6 months
- patients should be issued with an information booklet, alert card and record book
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