EpiPens Overview
An EpiPen is an epinephrine auto-injector used for anaphylaxis, a severe, life-threatening allergic reaction to things like insect stings, foods, medications or latex (MedlinePlus). It is not used for ordinary seasonal allergy symptoms such as sneezing or itchy eyes.
EpiPen is one brand name; others include Auvi-Q and generic auto-injectors (MedlinePlus). Epinephrine relaxes the muscles in the airways and tightens the blood vessels, which helps open the airways and raise blood pressure during anaphylaxis. Learn more about the medicine itself on our epinephrine page.
Anaphylaxis and Seasonal Changes
Seasonal allergies to pollen and mold cause symptoms like sneezing, a runny nose and itchy eyes. These are treated with antihistamines, nasal steroid sprays and avoiding triggers, not with an EpiPen.
Warmer months bring more stinging insects and outdoor eating, and stings and foods are common triggers of anaphylaxis. Anaphylaxis is rare but serious: symptoms can start suddenly and get worse quickly, and it needs emergency treatment. Symptoms can include:
- Tightening of the air passage, causing shortness of breath and swelling in the throat and tongue.
- Abdominal cramps
- Fainting or dizziness
- Extreme drop or rise in blood pressure
- Vomiting and diarrhea
- Worse skin conditions
Anaphylaxis should be treated immediately using an epinephrine injector, which is the first-line drug to treat anaphylaxis.
How Promptly Does An EpiPen Work For Anaphylaxis?
An auto-injector delivers epinephrine into the outer thigh muscle and works within minutes. Inject it as soon as you suspect a serious allergic reaction (MedlinePlus).
Delaying epinephrine can be dangerous. Keep two devices with you at all times, because one dose may not be enough (MedlinePlus). If you don’t have an auto-injector, call 911 immediately. Since 2024 there is also an FDA-approved needle-free epinephrine nasal spray (neffy) for people who weigh at least 30 kg (FDA).
After using epinephrine, get emergency medical treatment right away (MedlinePlus). Symptoms can last or come back hours later (biphasic anaphylaxis), so you need medical monitoring even if you feel better.
Side Effects of EpiPens
It is crucial to note any side effects when using EpiPen for the first time. Contact your physician immediately if you notice pain, rash, inflammation, warmth or other signs of infection around the injected area.
Some serious side effects include:
- Breathing difficulty
- Pounding, fast or irregular heartbeat
- Dizziness
- A pale and sweating body
- Severe weakness
- Nervousness or anxiousness
Don’t forget to inform your doctor next time you visit the hospital for any allergic symptoms.
Can Children Use EpiPens?
Auto-injectors come in different strengths for adults and children, often chosen by body weight. Ask your doctor which device and strength are right for your child, and check the product’s instructions for weight ranges.
Using EpiPens With Other Medical Conditions
Before using EpiPen, it is also important to let your doctor know about any other medical conditions you have or had in the past.
- Heart disease or unstable blood pressure
- Parkinson’s disease
- Asthma
- Depression, dementia or other mental diseases
- Thyroid disorder
- Diabetes
Anaphylaxis during pregnancy is dangerous for both mother and baby. If you are pregnant or breastfeeding, talk to your doctor ahead of time about your emergency plan, and always get emergency care after using an auto-injector.
How To Use EpiPens
The injector may be used differently for various brands. However, you should know how to operate it by reading the instructions on the leaflet given along with the injector. Check for the safety seal in the first place and do not use it if the seal in broken. Medicine in the injecter should be clear. If you visualize any particles or discoloration such as cloudy, pink or brown colour, then do not use it and discard it safely.
Keep the device in its carrying tube at room temperature, away from light, heat and moisture. Don’t refrigerate it or leave it in your car. Each device holds one dose. Replace it when it expires, and ask your pharmacist how to dispose of used or expired devices (MedlinePlus).
Inject only into the middle of the outer thigh; it can go through clothing in an emergency. Never inject into the hands, feet, buttocks or a vein. If that happens, get emergency treatment (MedlinePlus).
Conclusion
Epinephrine auto-injectors are the first-line emergency treatment for anaphylaxis. Know the difference between everyday seasonal symptoms and anaphylaxis, carry two devices, practice with a trainer device, and call 911 after every use. See also our seasonal allergy emergency guide and life-threatening vs. seasonal allergies.
Written by: Madiha Ather Hashmi (October 02, 2020)
This article is for general education and is not medical advice. Talk with your doctor or pharmacist about your symptoms and before starting, stopping, or combining any medicine.
EpiPen FAQs
Can I use an EpiPen for hay fever?
No. EpiPens are for anaphylaxis only. Hay fever is treated with antihistamines, nasal steroid sprays and avoiding triggers.
How many EpiPens should I carry?
Two, because one dose may not be enough (MedlinePlus).
Can I inject through clothing?
Yes. In an emergency you can inject into the outer thigh through clothing (MedlinePlus).
Can I keep my EpiPen in the car or fridge?
No. Store it at room temperature; don’t refrigerate it or leave it in a car (MedlinePlus).
Sources
- MedlinePlus, U.S. National Library of Medicine (revised June 2026). “Epinephrine Injection.”
https://medlineplus.gov/druginfo/meds/a603002.html - U.S. Food and Drug Administration (Aug. 2024). “FDA Approves First Nasal Spray for Treatment of Anaphylaxis.”
https://www.fda.gov/news-events/press-announcements/fda-approves-first-nasal-spray-treatment-anaphylaxis - Mayo Clinic. “Anaphylaxis: Symptoms and causes.”
https://www.mayoclinic.org/diseases-conditions/anaphylaxis/symptoms-causes/syc-20351468
Looking to learn more about allergy lifestyles? Find a full list of living with allergies resources here.