EpiPen® auto-injectors are automatic injection devices containing adrenaline for allergic emergencies.

The active ingredient and instructions for use are the same for EpiPen® and EpiPen® Jr so the information here is applicable for EpiPen® or EpiPen® Jr and the term EpiPen® is used throughout to refer to both interchangeably.

EpiPen® and EpiPen® Jr are indicated in the emergency treatment of severe allergic reactions (anaphylaxis) to insect stings or bites, foods, drugs and other allergens as well as idiopathic or exercise induced anaphylaxis.1,2

EpiPen® is an adrenaline auto-injector (AAI) used for self-administration of adrenaline for the emergency treatment of anaphylaxis.1,2

Below is a summary of the key features and benefits of EpiPen®:1,2

  • EpiPen® delivers the correct dose of adrenaline quickly
  • EpiPen® has needle protection which deploys immediately after administration
  • EpiPen® has familiar jab administration and only a 3 second injection hold time during administration in an emergency1,2
EpiPen® Auto-Injector Adrenaline concentration Body weight
EpiPen® 1 0.3mg (0.3ml, 1:1000) >25kg (3 st. 13 lbs.)
EpiPen® Jr 2 0.15mg (0.3ml, 1:2000) 7.5 – 25kg (1 st. 3lbs. – 3 st. 13lbs.)

Features

Viewing window

The EpiPen® must be replaced in line with the expiry date. In addition, check the EpiPen® regularly to make sure the solution is clear and colourless. If the solution becomes discoloured or contains particles it should be replaced.

Needle cover

This keeps the needle covered before and after use.

Flip top case

Designed for single-handed opening. The EpiPen® should be kept in its case when not in use.

How to use - instructions for patients
  1. Grasp EpiPen® auto-injector in dominant hand, with thumb closest to blue safety cap
  2. With the other hand pull off blue safety cap
  3. Hold the EpiPen® auto-injector at a distance of approximately 10 cm away from the outer thigh. The orange tip should point towards the outer thigh
  4. Jab firmly into the outer thigh, so that the EpiPen® auto-injector is at a right-angle (at a 90 degree angle) to the outer thigh
  5. Hold firmly in place for 3 seconds. The injection is now complete and the window of the auto-injector is obscured. The EpiPen® auto-injector should be removed (the orange needle cover will extend to cover needle) and safely discarded
  6. Call 999
  7. If symptoms have not improved or have deteriorated within 5 minutes after the first injection, use a second EpiPen.

When to use

Anaphylaxis is unpredictable and while a person may have a mild reaction one time, a serious or even life-threatening reaction can occur the next time. In addition, allergic reactions can begin with mild symptoms and then progress to a full anaphylactic episode.

A person who is having an allergic reaction should use their EpiPen® immediately if they experience ANY of the following serious symptoms of anaphylaxis following contact with their allergen:

  • Feeling light-headed or faint
  • Breathing difficulties, such as fast, shallow breathing
  • Wheezing
  • A fast heartbeat
  • Clammy skin
  • Confusion and anxiety
  • Collapsing or losing consciousness

Other allergy symptoms may include hives, feeling or being sick, angioedema or stomach pain.

Patients experiencing the following mild to moderate symptoms of anaphylaxis should take an anti-histamine and have their EpiPen® ready in case of worsening symptoms:

  • Red, raised, itchy rash
  • Swelling of face, lips or eyelids
  • Abdominal pain, nausea and/or vomiting
  • Tingling mouth

It is vital that patients carry 2 EpiPen® at all times. A second EpiPen® should be administered after 5 minutes if symptoms persist.1,2

Who should have an EpiPen®?

Absolute indications:3

  • Patients with previous anaphylaxis with food, latex, aeroallergens such as animals or other unavoidable triggers
  • Patients with co-existent, unstable or moderate to severe persistent asthma and a food allergy
  • Patients with exercise induced anaphylaxis
  • Patients with Idiopathic anaphylaxis
  • Venom allergy in adults with previous systemic reactions and children with more than cutaneous or mucosal systemic reactions
  • Patients with underlying mast cell disorders or baseline serum tryptase concentrations with any previous systemic allergic reactions to insect stings

The following indications should also be considered:3

  • Patients with previous mild-to-moderate allergic reaction to peanut and/or tree nut
  • Patients with previous mild-to-moderate allergic reaction to traces of food
  • Teenagers or young adults with food allergy
  • Patients who are remote from medical help and previous mild-to-moderate allergic reaction to food, venom, latex or aeroallergens

35% of patients may require more than one adrenaline dose.4

As many as 20% of patients will go on to develop a biphasic anaphylactic response many hours later.5

Undesirable effects.1,2

Repeated dose toxicity studies were not performed in conjunction with this application. Side effects associated with adrenaline's alpha and beta receptor activity may include palpitations, tachycardia, and hypertension as well as undesirable effects on the central nervous system, sweating, nausea and vomiting, respiratory difficulty, pallor, dizziness, weakness, tremor, headache, apprehension, nervousness and anxiety. Cardiac arrhythmias may follow administration of adrenaline.

Evaluation of undesirable effects is based on the following frequency information:

-Very common (>1/10)

-Common (>1/100 to < 1/10)

-Uncommon (>1/1 000 to < 1/100)

-Rare (>1/10 000 to < 1/1 000)

-Very rare (< 1/10 000)

-Not known (Frequency cannot be estimated from the available data)

  • rare cases of serious skin and soft tissue infections, including necrotizing fasciitis and myonecrosis caused by Clostridia (gas gangrene) are known from post-marketing experience

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

References

  1. EpiPen® (adrenaline) Auto-Injector 0.3mg Summary of Product Characteristics. Available at: https://www.medicines.org.uk/emc/product/4289/smpc. Last accessed: December 2024
  2. EpiPen® Jr (adrenaline) Auto-Injector 0.15mg Summary of Product Characteristics. Available at: https://www.medicines.org.uk/emc/product/4290/smpc. Last accessed: December 2024
  3. Muraro A, et al. EAACI guidelines: Anaphylaxis. 2022;77: 357-377
  4. Korenblat P et al. A Retrospective Study of Epinephrine Administration for Anaphylaxis: How Many Doses Are Needed? Allergy Asthma Proc. 1999;20(6):383-386
  5. Kemp, S.F et al. 2008. Epinephrine: the drug of choice for anaphylaxis--a statement of the World Allergy Organization. World Allergy Organization Journal, 1(S2), p.S18.