Lithium Overdose/Poisoning

Question 1

What is the typical cause of lithium overdose.

Answer 1

Usually the result of therapeutic overdose (chronic toxicity) rather than deliberate self-poisoning (acute toxicity).

Question 2

What are the clinical features of lithium toxicity. (11)

Answer 2

Thirst. 
Polyuria. 
Diarrhoea. 
Vomiting. 
Tremor. 
In more severe cases:
Impairment of consciousness. 
Hypertonia. 
Myoclonus. 
Fasciculations. 
Renal failure. 
Convulsions. 
(Irreversible neurological damage occurs).

Question 3

What are some causes of chronic toxicity of lithium. (2)

Answer 3

As a result of interactions with drugs such as diuretics or NSAIDs that can cause dehydration or renal impairment.
Because of an excessive dose has been prescribed.