lithium

Question 1

what type of drug is lithium?

Answer 1

mood stabiliser - mania,

Question 2

MOA of lithium?

Answer 2

unknown. Regulates catecholamine release in the CNS. Increase in noradrenaline and 5-HT uptake and decrease in noradrenaline from synaptic vesicles in pre-synaptic neuron. inhibits noradrenaline action in post synapatic neutron.

Question 3

contraindication of lithium?

Answer 3

addisons disease, dehydration, history of Brugada syndrome, low NA+ diet, untreated hyperthyroidism, cardiac insufficiency.

Question 4

side effects?

Answer 4

weight gain 33-66% but only in early stages due to food and fluid intake, lithium induced hypothyroidism, polyuria, polydispsia, tremor, CNS disturbance (drowsiness, giddiness), lack of co-ordination, impaired speech (dysarthria).

Question 5

monitoring requirements?

Answer 5

lithium-serum concentration. lithium salts have a narrow therapeutic/ toxic range. 04-8= maintenance and 0.8-1 for acute. Assess renal, cardiac and thyroid function before starting, ECG recommended. BMI/ weight, serum and electrolytes, eGFR every 6 months.

Question 6

treatment cessation?

Answer 6

abrupt discontinuation = risk of relapse. decrease over 4 weeks/ 3 months. Consider atypical / sodium valporate

Question 7

patient/ carer advice?

Answer 7

report signs of lithium toxicity, hyperthroidism, renal dysfunction, bengin intracrania; hypertension. maintain fluid intake and avoid dietary changes (increase/ decrease in sodium). lithium treatment pack- info booklet, lithium alert card, record book for tracking serum concentrations. Impairs driving.