N-acetylcysteine: risk of false-low biochemistry test results due to interference with Siemens assays

N-acetylcysteine may interfere with assays from Siemens ADVIA Chemistry and Dimension/Dimension Vista instruments, leading to false-low biochemistry test results.

Advice for healthcare professionals:

Professionals who are treating patients with N-acetylcysteine for paracetamol overdose should establish whether Siemens ADVIA Chemistry and Dimension/Dimension Vista instruments are used for laboratory testing of biochemistry and, if so, should:

  • do venipuncture and blood sampling before N-acetylcysteine administration; there is a risk of false low biochemistry test results and potential misinterpretation of physiological status if done during or immediately after administration

  • state if a patient is receiving N-acetylcysteine when requests for biochemistry tests (eg, cholesterol, uric acid, lactate) include any affected assays from these instruments

False low biochemistry test results may occur when testing samples drawn from patients receiving N-acetylcysteine for paracetamol overdose due to interference with the reaction assays of these Siemens instruments.

Further information, including a full list of affected assays, can be found in a medical device alert sent 22 June 2016.

Adverse incidents can be reported via: the Yellow Card Scheme in England and Wales; the Northern Ireland Adverse Incident Centre; or Health Facilities Scotland.

Article citation: Drug Safety Update volume 9 issue 12, July 2016: 3.

Published 18 July 2016