Lithium

Question 1

What use for lithium?

Answer 1

Treatment and prophylaxis of mania, bipolar disorder and recurrent depression

Question 2

Desired serum concentration for lithium? When is it toxic?

Answer 2

0.4 - 1mmol/L

Toxic - 1.5mmol/L+

Narrow therapeutic index

Question 3

Signs/symptoms of lithium toxicity? (7)

Answer 3

Tremor
Ataxia (shaky movements)
Dysarthria (speech disorder)
Nystagmus (shaky eyes)
Renal impairment
Convulsions
Blurred vision

Question 4

Lithium monitoring

Answer 4

Every 3 months: Lithium serum concentration

Every 6-12 months: Renal and Thyroid function

MAINTAIN SODIUM LEVELS

Question 5

Counselling for lithium

Answer 5

Maintain adequate FLUID intake and avoid dietary changes which reduce or increase SODIUM intake

Question 6

Lithium interactions

Answer 6

ACEi : reduces lithium excretion - risk of lithium toxicity

NSAIDs: reduces lithium excretion - risk of lithium toxicity (probs)

Diuretics (loop + thiazide): reduces lithium excretion - sodium depletion

Amiodarone: risk of ventricular arrhythmias