Hundreds of blood pressure pills have been recalled by health chefs on Friday, June 18, due to a serious public health risk. The drugs in question—several different types of irbesartan and losartan—were recalled from pharmacy shelves because they contain azido-tetrazole. According to some health experts, the substance is the world’s most explosive chemical and has been linked to increased cancer risk.

The Medicines and Healthcare products Regulatory Agency (MHRA) argued that the measure was just precautionary and that there was no evidence that it had caused any harm to patients. However, It warned Brits not to stop taking the medications without first consulting their doctor because stopping suddenly can be dangerous.

Dr. June Raine, the MHRA’s Chief Executive, commented on the decision, saying: “Patient safety is our watchword. We’re recalling batches of certain sartan-containing products as a precautionary measure while we continue our investigation. Healthcare professionals must check their stock to quarantine and return these batches.

“If you’ve been taking one of the affected products, speak with your doctor or pharmacist before stopping any treatment—they can address any concerns and can advise you on the best course of action.”

It’s the latest in a long line of sartan-type medicine recalls after cancer-causing compounds were found in medication manufactured in China and India.

Every year, millions of Britons with high blood pressure are offered irbesartan and losartan. Additionally, there is no proof that any of the pills have exploded.

According to the MHRA, the action only affected pharmacies and wholesalers who stock the 31 batches supplied by Bristol Laboratories Limited, Brown & Burk UK Limited, and Teva UK Limited, some of which were initially delivered in September 2019.

It’s worth noting that losartan and irbesartan-containing blood pressure pills are still accessible.

Previous recalls of these types of items in 2018 and 2019 are part of an ongoing investigation, according to Public Health England. The MHRA also stated that it is collaborating with other drug regulators on this concern.

Dr. Ljiljana Fruk of Cambridge University classified azido-tetrazole as the world’s “most explosive chemical” in 2019.

‘So the most explosive chemical was made in the lab in 2011,’ she stated on the Naked Scientists radio show.

‘[It] Never went out of the lab, it was made in a special chamber and it’s called azido-tetrazole.

‘So that’s a molecule that has 14 nitrogens in its own structure, and because of these constrained nitrogen bonds it’s very explosive.’

Officials have yet to explain what caused the latest impurity.

However, they are frequently brought on by contamination in factories or during the manufacturing or storage process.

Chemical changes can be triggered by exposure to light, extreme temperatures, or even reactions with the drug’s container.

Industry experts estimate that China and India produce more than two-thirds of all active drug components, with China accounting for the lion’s share.

In 2017, almost 2 million prescriptions for irbesartan-containing drugs were supplied in England, per the NHS figures.

It comes after a similar recall in January when carcinogenic chemicals were discovered in thousands of blood pressure pills on pharmacy shelves.

The FDA said in November that Aurobindo Pharma Ltd, an Indian pharmaceutical company, has recalled 22 products containing irbesartan due to concerns that they contained the N nitrosodiethylamine (NDEA) impurity, a chemical once used in rocket fuel.

As a precaution, EU officials said they were ‘considering’ recalling drugs containing the Indian firm’s irbesartan. Its ability to distribute the chemical to other European companies was then terminated.