A national alert has been issued after revelations that 5,000 wrongly labelled packs of diabetic testing strips have been sent out by a Basildon firm.

Patients who use the strips to check blood glucose level have been asked to check the packaging by company Waymade Healthcare which has since realised its blunder.

Instead of giving a reading for the glucose in the blood, as usual, the strips in question test for glucose in the plasma.

Brian McEwan, director of marketing for the company in Miles Gray Road, said the strips, which are used in parts of Europe, could record a reading up to 12 per cent higher.

He said: "It is not a huge difference and within the margins of error, but we want to err on the side of caution."

Around 4,200 packs bearing lot number 925722A and another 800 of lot 925724A have been distributed since February 21.

The packs are labelled as 'Whole Blood' with the words "procured from within the EU and repackaged by Waymade Healthcare Plc" on the side panel. The strip vials themselves are marked as "plasma calibrated".

Mr McEwan said: "For the vast majority of patients there should be no clinical significance. But it could scare them if they get a higher reading. In theory they could give themselves insulin unnecessarily. If patients are worried they should see their Health adviser."

Any patients in possession of packs should return them to their pharmacist to be exchanged.

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