Lithium

Question 1

what is the cut off for lithium toxicity

Answer 1

concentrations >1.5mmol/L

Question 2

what may lithium toxicity be precipitated by

Answer 2

• dehydration
• renal failure
• drugs: diuretics (especially thiazides), ACE inhibitors/angiotensin II receptor blockers, NSAIDs and metronidazole.

Question 3

what are the features of lithium toxicity

Answer 3

coarse tremor (a fine tremor is seen in therapeutic levels)
hyperreflexia
acute confusion
polyuria
seizure
coma

Question 4

what is the management of mild-moderate lithium toxicity

Answer 4

IV fluids with isotonic saline, until euvolemic, then typically twice maintenance rate
monitor serum sodium closely (every 4 hours with serial lithium concentrations)

Question 5

what is the management of severe lithium toxicity

Answer 5

haemodialysis and sodium bicarbonate