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Allergies: When to Use Your Auto-Injector

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You can’t predict allergic reactions. They can be mild one time and serious the next. An attack can quickly become intense, sometimes leading to anaphylaxis -- a severe, often life-threatening reaction. An auto-injector -- such as EpiPen, Twinject, or Auvi-Q -- can treat extreme allergic reactions with an early, life-saving dose of epinephrine.

Epinephrine is adrenaline, a hormone your body naturally produces. Among other things, it can help improve breathing, raise blood pressure that’s dropping, and reduce swelling.

When you or a loved one has an allergic reaction, it’s common to wonder if the shot is needed. Experts say if there's any doubt, use the device. It’s much more dangerous not to get epinephrine when you’re having a severe reaction than to get a dose you don’t really need.

Keep the Injector Handy and Ready

The device won't do you any good if you don't have it with you. When you pick up your prescription at the drugstore, you'll get two injectors. Carry both with you at all times in case one doesn’t work or you have a reaction that requires more medication.

Extreme heat and cold can cause the medication not to work, so store devices at room temperature. Don’t leave them in your car.

The injectors are usually good for a year, so keep track of the date on the box.

When to Take the Shot

There are many cases when you, or someone you know, would need to use the auto-injector, but two general ones are:

1) If you have a life-threatening allergy and you know you’ve been exposed. An example: If you have a peanut allergy and your boyfriend ate some peanuts and then kissed you, don't wait for symptoms -- take the epinephrine right away.

2) If you're experiencing allergy symptoms -- even if you don’t know the trigger.

Those symptoms can include:

What to Do After a Shot

Take these steps after the first injection:

  • If there's no relief, take a second dose. You could wait as few as 5 minutes for a severe reaction or 15 minutes if it is mild .
  • Have someone call 911.
  • Massage the injection site for 10 seconds to stimulate blood vessels and help the body absorb the medication.
  • Go to the emergency room after an injection, even if symptoms improve or seem to go away. Severe episodes can last 4 to 12 hours, and you never know at the beginning how long yours will last.

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