Epinephrine injection is used to treat severe allergic reactions (anaphylaxis) to insect stings or bites, foods, drugs, and other allergens. Epinephrine is also used to treat low blood pressure that is caused by septic shock.

Epinephrine injection works to reverse wheezing, severe skin itching, hives, and other symptoms of an allergic reaction and also helps with severely low blood pressure. Epinephrine is a is a hormone and neurotransmitter that acts on alpha and beta receptors to cause the muscles in the airways to relax, and it causes the blood vessels to narrow. Epinephrine is from the drug class of medicine called sympathomimetics.

Epinephrine auto-injectors may be kept on hand for self-injection by a person with a history of severe allergic reactions. An Auto-Injector is a hand-held device that automatically injects a measured dose of medicine, it is easier to use in an emergency compared to using vials and needles. 

Epinephrine is also known as adrenaline and adrenalin. 

Seek emergency medical attention after any use of epinephrine to treat a severe allergic reaction. After the injection, you will need to receive further treatment and observation.

Follow all directions on your prescription label and read all medication guides or instruction sheets before you need to use it  Ask your doctor or pharmacist if you need help. Use the medicine exactly as directed.

Epinephrine is usually injected as needed at the first sign of a serious allergic reaction. 

Epinephrine is injected into the skin or muscle of your outer thigh. In an emergency, this injection can be given through your clothing.

This medicine may come with a "trainer pen." The trainer pen contains no medicine and no needle. It is only for non-emergency use to practice giving yourself an epinephrine injection.

Seek emergency medical attention after any use of epinephrine. The effects of epinephrine may wear off after 10 or 20 minutes. You will need to receive further treatment and observation.

Also seek emergency medical attention if you accidentally inject yourself while giving epinephrine to another person.

Do not give this medicine to a child without medical advice.

The auto-injector device is a disposable single-use system. Use an auto-injector only one time.

Do not try to reinsert an auto-injector a second time. If the needle is bent from the first use, it may cause serious injury to your skin.

Do not use the injection if the expiration date on the label has passed. Call your pharmacist for a new prescription.

Do not reuse a needle or syringe. Place them in a puncture-proof "sharps" container and dispose of it following state or local laws. Keep out of the reach of children and pets.

What should I avoid while using epinephrine injection?

Do not inject epinephrine into a vein or into the muscles of your buttocks, or it may not work as well. Inject it only into the fleshy outer portion of the thigh.

Accidentally injecting epinephrine into your hands or feet may result in a loss of blood flow to those areas, and resulting numbness. You should seek emergency help immediately.

Usual Adult Dose for Anaphylaxis

Auto-Injector:
30 kg or greater: 0.3 mg IM or subcutaneously into the outer thigh (upper leg), repeat as needed.

Comments:

• The manufacturer's product information for the specific auto-injector being used should be consulted for administration instructions.
• More than 2 sequential doses should only be administered under direct medical supervision.
• The auto-injectors are intended for immediate administration as emergency supportive therapy only and not as a replacement or substitute for immediate medical care.

Injectable Solution of 1 mg/mL (1:1000):

30 kg or greater: 0.3 to 0.5 mg (0.3 to 0.5 mL) of undiluted drug IM or subcutaneously into the outer thigh (upper leg), repeat every 5 to 10 minutes as needed.

• Maximum dose per injection: 0.5 mg (0.5 mL).

Comments:

• For IM administration, use a long enough needle (at least 1/2 inch to 5/8 inch) to ensure injection into the muscle.
• Repeated injections should not be administered at the same site as resulting vasoconstriction may cause tissue necrosis.
• The patient should be monitored clinically for reaction severity and cardiac effects with repeat doses titrated to effect.

Injectable Solution of 0.1 mg/mL (1:10,000):

0.1 to 0.25 mg (1 to 2.5 mL) IV slowly once.

Convenience Kit 1 mg/mL (1:1000):

0.2 to 1 mg IM or subcutaneous.

Usual Pediatric Dose for Anaphylaxis

Auto-Injector:
7.5 to 15 kg: 0.1 mg IM or subcutaneously into the outer thigh (upper leg), repeat as needed.
15 to 30 kg: 0.15 mg IM or subcutaneously into the outer thigh (upper leg), repeat as needed.
30 kg or greater: 0.3 mg IM or subcutaneously into the outer thigh (upper leg), repeat as needed.

Comments:

• Since the lowest dose of the auto-injector is 0.1 mg, consider using other injectable forms of this drug if doses lower than 0.1 mg are necessary.
• More than 2 sequential doses should only be administered under direct medical supervision.
• The manufacturer product information for the specific auto-injector being used should be consulted for administration instructions.

Injectable Solution of 1 mg/mL (1:1000):

Less than 30 kg: 0.01 mg/kg (0.01 mL/kg) of undiluted drug IM or subcutaneously into the outer thigh (upper leg); repeat every 5 to 10 minutes as needed

• Maximum dose per injection: 0.3 mg (0.3 mL)

30 kg or greater: 0.3 to 0.5 mg (0.3 to 0.5 mL) of undiluted drug IM or subcutaneously into the outer thigh (upper leg), repeat every 5 to 10 minutes as needed

• Maximum dose per injection: 0.5 mg (0.5 mL)

Comments:

• For IM administration, use a long enough needle (at least 1/2 inch to 5/8 inch) to ensure injection into the muscle.
• Repeated injections should not be administered at the same site as resulting vasoconstriction may cause tissue necrosis.
• The patient should be monitored clinically for reaction severity and cardiac effects with repeat doses titrated to effect.

Injectable Solution of 0.1 mg/mL (1:10,000):

• Neonate: 0.01 mg/kg IV slowly once
• Infant: 0.05 mg IV slowly once; may repeat at 20 to 30 minute intervals as needed

Uses: For the emergency treatment of allergic reactions (Type I) including anaphylaxis to stinging or biting insects, allergen immunotherapy, foods, drugs, diagnostic testing substances, and other allergens, as well as idiopathic anaphylaxis or exercise-induced anaphylaxis; and for immediate administration in patients who are determined to be at increased risk for anaphylaxis, including those with a history of anaphylactic reactions.

Epinephrine injection Dosage information (more detail)

Before using epinephrine auto injector or injection, tell your doctor if any past use of epinephrine injection caused an allergic reaction to get worse.

Tell your doctor if you have ever had:

• heart disease or high blood pressure;
• asthma;
• Parkinson's disease;
• depression or mental illness;
• a thyroid disorder; or
• diabetes.

Having an allergic reaction while pregnant or nursing could harm both mother and baby. You may need to use epinephrine during pregnancy or while you are breastfeeding. Seek emergency medical attention right away after using the injection.

If possible, during an emergency, tell your medical caregivers if you are pregnant or breastfeeding.

Since epinephrine is used when needed, it does not have a daily dosing schedule.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include numbness or weakness, severe headache, blurred vision, pounding in your neck or ears, sweating, chills, chest pain, fast or slow heartbeats, severe shortness of breath, or cough with foamy mucus.

Before using epinephrine, tell your doctor if any past use of epinephrine injection caused an allergic reaction to get worse.

Call your doctor at once if you notice pain, swelling, warmth, redness, or other signs of infection around the area where you gave an injection.

Side effects may be more likely in older adults.

Common side effects of epinephrine injection may include:

• breathing problems;
• fast, irregular, or pounding heartbeats;
• pale skin, sweating;
• nausea and vomiting;
• dizziness;
• weakness or tremors;
• headache; or
• feeling restless, fearful, nervous, anxious, or excited.

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See more: Epinephrine injection Side Effects

Tell your doctor about all your other medicines, especially:

• asthma medicine;
• an antidepressant;
• cold or allergy medicine (Benadryl and others);
• heart or blood pressure medicine;
• thyroid medication; or
• ergot medicine--dihydroergotamine, ergotamine, ergonovine, methylergonovine.

This list is not complete. Other drugs may affect epinephrine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.