Look-alike Drugs

The ampoule on the left contains glycopyrrolate, a medication commonly used during general anaesthesia as part of the process of waking the patient at the end of surgery.

The ampoule on the right contains oxytocin, a medication which is used to make the uterus contract in a variety of different situations.

In addition to the obvious similarity between these ampoules, having the text printed directly on glass makes them difficult to read, particularly given their small size.

Whilst glycopyrrolate can be safely administered to a pregnant woman having an anaesthetic, inadvertent substitution of the equivalent volume of oxytocin will result in severe uterine contractions, likely to cause serious harm or death to the unborn foetus.

Normal saline (0.9% sodium chloride) is a mixture of water and electrolytes that does not contain any drugs. It has no pharmacological effect on the body when administered intravenously.

Local anaesthetics are injected close to nerves to numb parts of the body & reduce pain. Administered intravenously in sufficient doses, however, local anaesthetics can cause seizures & cardiac arrest.

The top picture shows two bags of normal saline on the left & a bag of local anaesthetic on the right. Intravenous fluids such as normal saline commonly come in a variety of sizes and shapes so it is forseeable that this packaging could result in the inadvertent administration of intravenous local anaesthetic with potentially life threatening consequences.

The following are just a few examples of “look-alike packaging”. All of these are currently occurring in Australia, New Zealand or the United Kingdom. At this moment, patients are being exposed to the risks described below.

Aspen Pharma Austraila have agreed to change the colour of the text on the oxytocin ampoule to purple, to improve the ability to distinguish between these two drugs. The realities of the manufacturing process, however, mean that the revised packaging will not be available in hospitals until April 2015, during which time patients remain exposed to the risk of being subjected to this error.

As a result of “near miss events” multiple Victorian Healthcare Networks have been submitting concerns about this packaging since September 2014. As such, by the time the improved packaging comes into effect, patients will have been exposed to the risks of this “lookalike packaging” for over 6 months.

This underscores the need for mandatory packaging requirements to prevent packaging like this being allowed to be released in the first instance.

The lower image depicts two ampoules, the upper one contains normal saline (0.9% sodium chloride) and the lower a local anaesthetic agent. Again the similarity of the packaging increases the potential for unintentional intravenous administration of local anaesthetic.

Although these three ampoules look very similar, they contain very different medications.

Atracurium (left) is a muscle relaxant that temporarily paralyses the body’s muscles, leading to inability to move or breathe. It should only ever be administered to unconscious patients by specialists with the skills & equipment available to breathe for the patient. Inadvertent administration of muscle relaxants such as atracurium to awake patients can lead to “awake paralaysis” (being fully aware of your surroundings but being unable to move, speak or breathe) and, if not recognised rapidly, hypoxic brain damage & death.

Phenytoin (middle) is an anticonvulsant medication used to prevent and treat seizures.

Flumazenil (right) is a drug used to the reverse the effects of some sedatives.

All of these drugs have the potential to cause dangerous side effects if given accidentally. Additionally when substitutions of “look-alike medications” occur, there is the potential for harm to result from the omission of the intended drug if the error is not recognised. For example, inadvertent administration of atracurium to a patient experiencing seizures would appear to terminate the seizure (due to the onset of muscle paralysis) whilst the electrical seizure activity in the brain would remain untreated, with potentially harmful neurological effects.

“Look-alike Drugs”

Read this BBC News report on patient deaths which have occurred as a result of

substitution of intravenous fluids with local anaesthetic

Conversely, whilst inadvertent substitution of sodium chloride solutions for local anaesthetic will not have any adverse pharmacological effects, it will result in unnecessary pain for the patient.

Read this report in The Age about the consequences of accidental administration of high dose

oxytocin in pregnancy