Medication error alert – cyanide antidote packaging mix-up

All NHS hospitals in England have been told to destroy a powerful medicine after health care staff in England mistakenly used it because its packaging looks the same as another drug.

A national safety alert was issued following several incidents, including the deaths of two babies at hospitals in England, in which patients were inadvertently given a dose of sodium nitrite – which is used as an antidote to cyanide poisoning – rather than sodium bicarbonate.

The errors are thought to have been caused by similarities between the labelling and drug packaging used by manufacturers.

Sodium nitrite can cause significant side effects, including methaemoglobinaemia and nitric oxide induced vasodilation; with Toxbase categorising it as ‘highly toxic’.

Historically, sodium nitrite 30mg/ml has been an unlicensed product supplied in ampoules by ‘Specials’ manufacturers.4 However a licensed product, supplied as a vial, has been available since 2016.

NHS acute trusts are asked to remove sodium nitrite injections from all clinical areas except Emergency Departments, and replace unlicensed sodium nitrite ampoules with licensed sodium nitrite vials. Pharmacies and Emergency Departments are also asked to change procedures and storage policies for all ‘specialist antidotes’.

Since May 2018, five incidents have been reported by NHS staff in which confusion of drugs happened. Two involved premature babies who needed sodium bicarbonate to help reduce acidosis in their blood. One baby died soon after the medication was given, while a second died later in neonatal intensive care.

In two other incidents, the drug was mistakenly used in place of medicine to treat high blood pressure. The patients did not suffer significant harm.

The problem of similarities in drug packaging on busy, often short-staffed, medical wards is recognised as a persistent patient safety issue around the world. As a result of this latest alert, NHS England said it would be looking at how drug “specials” are packaged and labelled by manufacturers as there is a wider concern the problem could affect other drugs.