Blood Sciences Test


Amiodarone

Specimen

EDTA (trough level – ideally taken just before the next dose)

Special Instructions

Please provide details of the dose, the time of the last dose and the time the blood was taken.

Units

umol/L

Test Usage

Test Usage This drug is a class III anti-arrhythmic (lengthens refractoriness without affecting sodium inflow). It is slowly absorbed after oral administration with peak levels occurring after 3 – 7 hours. It is 96% protein bound and has a very large volume of distribution (62 l/kg) – thus giving a very long half life (a single dose may give a t1/2 of 10 – 40 days; the t1/2 after chronic therapy may exceed 100 days). Because of the slow absorption, samples should be take neither just before (ideal) or just after the dose.

Routine monitoring is not recommended, but measurement may be of value in assessing possible toxicity.

More importantly, regular (6 monthly) checking of liver function should be an integral part of amiodarone treatment. It is advisable to check baseline thyroid function tests before starting therapy, as this drug may precipitate either hypo- or hyperthyroidism.

Availability

Referred test

Turnaround Time

21 days

 

Specimen Labelling Procedure