Following a recent European review, the Medicines and Healthcare products Regulatory Agency (MHRA) has issued a drug safety update on adrenaline auto-injectors.
Following a recent European review into the devices, the MHRA makes the following recommendations:
- Prescribe two adrenaline auto-injectors to patients with allergies, which they should carry at all times (particularly important if they have allergic asthma),
- Patients and carers must be trained to use the particular auto-injector they have been prescribed (as technique differs by device),
- Patients and carers should also practice using the injector using a trainer device, which are available for free from the manufacturers website,
- Use the auto-injector at the first signs of a severe allergic reaction,
- Always obtain replacement injectors before they expire.
Failing to use an adrenaline auto-injector properly could be fatal. Symptoms of anaphylaxis include swelling in the throat, wheezing and feeling faint. Side-effects of using the device when not necessary include palpitations, a rapid heartbeat, anxiety and high blood pressure, although this is much less dangerous then failing to use the device when necessary.
Training is key
The European Medicines Agency (EMA) review looked at all adrenaline auto-injectors approved in the EU and identified uncertainties about the site of drug delivery and speed of action.
In particular, it was concerned that devices may be delivering the drug under the skin rather than into muscle, which can delay its action.
It found several factors that can affect delivery, including needle length (which is now stated in the product information), thickness of fat in the patient, how the particular device works and how well the user follows the instructions.
To improve the use of adrenaline auto-injectors, the EMA said manufacturers should provide better training materials for users and carry out clinical studies to understand when and how much adrenaline reaches the blood stream and how quickly it acts.
It also said prescribers of auto-injectors should make sure patients fully understand how and when to use the device and go through instructions with them.
An updated advice sheet on the use of adrenaline auto-injectors is available here.