Priadel, Camcolit, Liskonum
Lithium is use in the prophylaxis of mood disorders,
specifically depressive illness. Concentration monitoring is
essential when therapy is initiated; once therapy is established,
routine monitoring is advocated at 3 to 6 monthly intervals.
For individual patients, serum concentration and dose are linearly
related which makes dose adjustment easier. Thyroid function
and creatinine should also be measured at least annually.
Peak absorption occurs within 2-4 hours after oral dose, with
complete absorption after 8 hours. Lithium is virtually unbound to
plasma proteins and is freely filtered by the glomerulus where it
is reabsorbed by the same mechanism as sodium in the proximal
Half-life varies with age from 8-20 hours in younger patients with
normal renal function, increasing to 30-40 hours in the elderly or
in patients with impaired renal function.
Request on ICE
Please state time after last dose on request form.
On request during routine hours. Laboratory must be contacted
regarding urgent requests.
Samples should be taken 12 hours after last dose.
Steady state levels are achieved 2-5 days following a change in
Do not use lithium heparin tubes
Samples should be analysed same day if left on gel
Causes for Rejection
Unlabelled or incorrectly labelled sample
Collected too soon after last dose
0.4 to 1.0 mmol/L. Effective prophylaxis can be achieved in most
patients with levels of 0.5 to 0.8 mmol/L at 12 hours post
Concentrations above 1.4 mmol/L may exertnephrotoxic effects,
which leads to decreased elimination and serum levels rise still
Lithium concentrations above 2.5 mmol/L are associated with
significant mortality, especially if they arise as a result of
gradual build-up on regular therapy rather than acute overdose.
In acute cases measure the lithium level at 6 hours and repeat
6-12 hourly. For acute on chronic or chronic accumulation measure
the serum lithium concentration immediately and at 6 hours, then
repeat 6-12 hourly. Do not use lithium-heparin tubes
for the sample.