What happens if you use an Epipen without needing it?

The American College of Allergy, Asthma, and Immunology recommends using an EpiPen (generic name: epinephrine) even if you are not sure if it is needed, because the benefits greatly outweigh the risk that you might not need it.

While an EpiPen is a life-saving device for individuals with severe allergies, using it unnecessarily can lead to certain side effects. These side effects typically include:

• Increased heart rate
• Increased blood pressure
• Headache
• Tremors
• Anxiety or nervousness

These side effects of using an EpiPen accidentally are usually temporary and less severe than the consequences of a severe allergic reaction. Some people with certain health problems might be at a higher risk for experiencing more severe side effects (e.g., abnormal heart rhythm, excess fluid in the lungs). Consult with a healthcare professional about when it is appropriate to use an EpiPen.

How soon will I feel the effects after using an EpiPen?

Studies of healthy adults not having an allergic reaction who took a dose of the EpiPen noticed effects 1 minute after using it. This is because unlike oral medication, it is injected directly into a muscle or under the skin.

What does an EpiPen do to a regular person?

If you accidentally use an EpiPen without needing it, your heart rate and blood pressure will go up within minutes. Other side effects you may experience include:

• Anxiety
• Restlessness
• Tremor
• Dizziness
• Sweating
• Headache

Additionally, your thigh might feel sore in the area where you injected the EpiPen. Get medical attention if you notice any side effects that seem severe.

Accidental injection into fingers and hands

While an EpiPen is designed for use on the outer thigh muscle, accidental injection into the fingers, hands, or feet may occur. These areas have smaller blood vessels, so epinephrine’s strong vasoconstrictor effect can significantly decrease blood flow. This can lead to numbness, pain, or even tissue injury if untreated.

If epinephrine is injected into these areas, it is important to seek prompt medical care, as severe cases may require treatment with medications to reverse the constriction and restore blood flow.

Who is at higher risk for serious side effects?

Most healthy adults and children will only experience temporary symptoms, such as a racing heart or mild headache, if they use an EpiPen without needing it. However, certain people are more vulnerable to potentially serious adverse effects, including:

• Older adults (due to increased likelihood of heart disease)
• People with pre-existing heart conditions, arrhythmias, or high blood pressure
• Those with hyperthyroidism, diabetes, or blood vessel diseases

In these individuals, epinephrine can exacerbate heart problems, increase blood pressure, and occasionally cause irregular heartbeats or even chest pain. Close monitoring and medical supervision are advised if unnecessary epinephrine is given in high-risk populations.

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Rare and serious complications

Unintended use of an EpiPen is almost always safe in emergencies, but rare complications have been documented in medical literature. Severe outcomes are more likely in individuals with underlying health concerns or after accidental overdose. These include:

• Severe high blood pressure
• Dangerous heart rhythms
• Fluid in the lungs (pulmonary edema)
• Reduced blood flow to vital organs

Immediate overdose of epinephrine may present as a change in heart rate, paleness, trouble breathing, or weakness. Call for emergency help if any of these symptoms occur.

What to do after accidental or unnecessary EpiPen use

If someone uses an EpiPen but does not have a severe allergic reaction, the following steps are recommended:

• Stay calm and rest, as most side effects like jitteriness or increased heart rate resolve within a few hours.
• Monitor for more serious symptoms such as chest pain, difficulty breathing, lasting paleness or weakness, or any neurological changes.
• For accidental finger or hand injections, seek immediate medical attention even if there is no pain, as tissue damage can occur if left untreated.
• For injection site discomfort (thigh), pain and swelling may last a couple of days and can be managed with over-the-counter pain relief and cool compresses.

How long do side effects from EpiPen last?

Most side effects from a dose of EpiPen should go away within a few hours after using it. The effects of the medication typically start to wear off within 30 minutes. In a study of healthy adults who took a dose of the EpiPen, blood pressure returned to normal within 120 minutes. Pain where you injected the medication into your thigh should feel better within a few days.

If you believe you may be having a severe allergic reaction, it is essential to use your EpiPen immediately and seek emergency medical attention.

This is not all the information you need to know about EpiPen (epinephrine) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.

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• EpiPen user reviews (11)

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