Roche's Valium hit by tampering in Australia

Roche has issued a nationwide recall for its Valium brand of anxiety medicine in Australia after packs were discovered that had been tampered with, the tablets replaced with other medicines.

Australian regulatory authority the Therapeutic Goods Administration (TGA) said it was working with Roche on the recall of all Valium (diazepam) 5mg tablets in 50-count blister packs after some were discovered with painkillers, cholesterol-lowering drugs, gastrointestinal medicines and anti-nausea agents.

Diazepam is used to treat anxiety disorders, alcohol withdrawal symptoms and muscle spasms, and substituting the tablets for other medicines could mean patients do not have adequate supplies of their medicine and could potentially suffer serious health consequences from taking the wrong drug.

Packs were found containing painkillers paracetamol and codeine, the lipid-lowering drug rosuvastatin, pantoprazole for esophagitis and prochlorperazine maleate – used to treat nausea and vomiting. The TGA said it was not ruling out the possibility that other substituted medicines may be discovered in the tampering case.

The cause of the tampering remains a matter of speculation, as is often the case in such incidents. "The issue is currently being investigated in conjunction with the relevant authorities," said the TGA in a statement. "However, it is believed that the tampering is not widespread."

The agency advises users of Valium to return their medication to pharmacies for a refund or replacement. It also says consumers should pay attention to discrepancies in their medication and stresses that all tablets or capsules should be identical.

Thankfully incidents of this type of tampering are pretty rare, but the risk to consumers is significant as of course is the cost to companies for recalls. In 2014, GlaxoSmithKline (GSK) ordered a recall of its weight-loss product Alli in the US and Puerto Rico, after bottles were discovered containing a range of different medicines, and it was a year before the product was returned to the shelves with new tamper-evident packaging.

Meanwhile, two years previously Reckitt Benckiser was forced to recall stocks of painkiller Nurofen Plus from UK pharmacies and retail outlets after packs were found to contain a schizophrenia drug. In that incident – which cost the company an estimated $4m – the culprit was found to be swapping his prescribed medicine for the tablets in stores to feed an addiction to codeine.