TAINTED batches of generic lamotrigine tablets, used for treating bipolar disorder and epilepsy, are being dispensed in Australia, research from the University of NSW (UNSW) reveals.
The study published in Australasian Psychiatry used mass spectrometry to analyse six lamotrigine preparations distributed in Australia and two generic versions of the drug used by two patients reporting side effects.
While the analyses of the six preparations were comparable and showed no signs of compromising, the assays of the drugs taken by the two patients showed deviations in the lamotrigine concentration.
Lead author, UNSW Medicine and Health School of Clinical Medicine Scentia Professor of Psychiatry, Gordon Parker, noted that the findings did not suggest "that all generics are universally compromised".
"But our analyses do indicate some compromised lamotrigine medications are being distributed in Australia," he said.
"It's possible that being transported to Australia, they might be exposed to excessive heat or cold and may break down.
"But we suspect there are some manufacturing sites where the product is being compromised or contaminated after receiving Therapeutic Goods Administration (TGA) approval.
"The faulty batches likely reflect some on-site manufacturers having poor quality control processes, and the pharmaceutical companies may be quite unaware of what's going on with their manufacturers."
Parker noted that the TGA received 114 adverse event reports for lamotrigine, including four deaths, between Jan 2018 and Feb 2021, but said the regulator had yet to take action.
"This should signal a possible canary in the coal mine phenomena that the TGA should be urgently looking into," he said.
The above article was sent to subscribers in Pharmacy Daily's issue from 01 Dec 22
To see the full newsletter, see the embedded issue below or CLICK HERE to download Pharmacy Daily from 01 Dec 22