Lithium

Question 1

when lithium blood levels are established, how often should they be checked ?

Answer 1

every 3 months

Question 2

after a dose change, how often should lithium levels should be checked?

Answer 2

1 week after the dose change

then weekly until levels are stable

Question 3

when starting lithium, how often should blood levels be monitored ?

Answer 3

check blood level weekly and after each dose change until concentrations are stable

Question 4

apart from lithium blood levels, what else should be monitored in a patient who is on lithium and why ?

Answer 4

thyroid and renal function checked every 3 months

risk of thyroid enlargement = hypothyroidism
nephrotoxicity

Question 5

when checking lithium blood level, the is the correct time to check levels ?

Answer 5

12 hours post-dose

Question 6

adverse effects of lithium ?

Answer 6

nausea/vomiting, diarrhoea
nephrotoxicity
- polyuria due to nephrogenic diabetes insipidus
thyroid hyperplasia - may lead to hypothyroidism 
leukocytosis 
hyperparathyroidism = hypercalcaemia
idiopathic intracranial hypertension 
fine tremor 
ECG: T wave flattening/ inversion 
weight gain

Question 7

what ECG feature can lithium cause ?

Answer 7

T wave flattening/inversion

Question 8

what is the therapeutic range of lithium ?

Answer 8

0.4 - 1.0 mmol/L