How to recognize signs of anaphylaxis and 8 life-saving steps to take during this severe allergic reaction

• Anaphylaxis can cause severe itching, difficulty breathing, fainting, and abdominal pain.
• These symptoms usually begin about 30 minutes after coming into contact with an allergy trigger.

If you have allergies, you might be very familiar with all those annoying — but usually manageable — symptoms, like itchy, sore eyes and a runny nose.

In some cases, though, allergies can cause anaphylaxis, an extreme, life-threatening reaction.

Up to 5% of people in the US will experience anaphylaxis at some point in life. It most often happens after exposure to a handful of common allergy triggers, including certain foods, medications, insect stings, and latex. But any allergen can cause this reaction.

Even though anaphylaxis can lead to dangerous symptoms like swelling in your throat or low blood pressure, most people will recover — just 0.3% of hospitalized cases are fatal.

However, anaphylaxis is always an emergency and requires prompt medical attention.

That's why it's essential to know the signs so you can act quickly to find emergency treatment if you, or someone close to you, experiences anaphylaxis.

Symptoms

Anaphylaxis symptoms usually start within 5 to 30 minutes of exposure, says Dr. Sandra Bonat, pediatric advisor at VIP Star Network.

Note: In some cases, symptoms may show up within seconds after exposure, but sometimes, you may not have symptoms for hours.

Symptoms can range from mild to severe and often begin with severe itching in the eyes or face, Bonat says.

You may also experience:

• Swelling in your throat or airways, which can make it hard to breathe or swallow
• Hives
• Shortness of breath
• Wheezing
• Abdominal pain
• Feeling of dread
• Diarrhea
• Vomiting
• A drop in blood pressure
• Weak pulse
• Loss of consciousness
• Shock

What to do: 8 life-saving steps

When anaphylaxis occurs, you need to treat it with epinephrine, aka adrenaline. Epinephrine quickly works to stop severe, life-threatening symptoms, like swelling in your throat or low blood pressure.

People who have a high risk of anaphylaxis often carry an automatic epinephrine injector, like an EpiPen or Auvi-Q.

If you notice someone experiencing symptoms of anaphylaxis, take action right away — do not wait for their symptoms to improve.

"The quicker they receive treatment, the better the outcome," says Dr. Duyen Nguyen, an allergist at Memorial Hermann.

If someone near you shows signs of an anaphylactic reaction, you can help them by following these eight steps:

1. First, call 911.

2. Ask the person if they carry an epinephrine auto injector.

3. Help them use their auto injector if they can't do it themselves. Usually, you'll press the injector against their thigh and then inject the medication. You can give the injection through clothes or directly into their skin, but don't inject into a vein.

4. Help the person lie down with their face up. They should stay still.

5. Loosen any tight clothing and cover them with a blanket or jacket, if you have one.

6. Avoid giving them anything to drink.

7. If they are vomiting or bleeding from the mouth, turn them to their side to prevent choking.

8. If they don't seem to be breathing, start CPR: Press down firmly into the middle of their chest about 100 times per minute — If this feels difficult to track in the moment, the American Heart Association suggests doing chest compressions to the beat of the song "Stayin' Alive."

Important: Make sure to seek emergency medical treatment, even if they take their epinephrine and begin to feel better, Bonat says. They need to go to the emergency room to make sure their symptoms don't come back, which can happen in biphasic anaphylaxis.

If you start to experience symptoms of an anaphylactic reaction:

1. Call 911 immediately or find someone to call for you.

2. Tell people around you that you're having an emergency allergic reaction and ask if anyone carries epinephrine.

3. Inject epinephrine into your thigh, if it's available.

4. Sit or lie down and wait for emergency help to arrive.

Emergency responders will give you epinephrine if you haven't already injected it.

If you still can't breathe, they may use other emergency treatments to give you oxygen. For example, they might place a tube through your mouth or nose, or directly into your windpipe by making an incision in your neck.

Once you're stabilized, a doctor or other healthcare professional may:

• Give you medicine to reduce your symptoms, including antihistamines, like Benadryl, and steroids, like prednisone.
• Recommend skin or blood allergy tests to confirm what substance or allergen triggered the reaction.
• Prescribe an epinephrine auto injector for you to use in the case of any future anaphylactic reactions and recommend you carry it with you at all times.

Why does it happen?

Normally, allergies give you mild symptoms like a runny nose or itchy eyes.

But with anaphylaxis, your immune system overreacts when you come into contact with something you're allergic to. Chemicals released by your immune system, such as histamine and prostaglandin D, can cause severe symptoms like difficulty breathing and a rapid heart rate.

Foods are the most frequent cause of anaphylaxis. The most common culprits include:

• Shellfish
• Cow's milk
• Eggs
• Soy
• Fish
• Tree nuts, like walnuts and hazelnuts
• Wheat

Other allergens known to trigger anaphylaxis include:

• Venom from insect stings — most commonly bees and wasps
• Latex in gloves, adhesives, and other products
• Some medications, like antibiotics, non-steroidal anti-inflammatory drugs (NSAIDS), and dye used in computerized tomography (CT) scans

A few factors may increase your risk of anaphylaxis, such as:

• A previous anaphylactic reaction
• A history of allergies or asthma
• Underlying health conditions, like heart disease or mastocytosis — an irregular accumulation of a type of white blood cell.

Preventing anaphylaxis

The most important thing you can do to prevent anaphylaxis involves strictly avoiding things you're allergic to, Nguyen says.

So, depending on your known allergy triggers, you may want to:

• Carefully read ingredient labels on foods. Ask restaurants what ingredients they use and how they prepare their dishes.
• Wear long sleeves, long pants, and shoes that completely cover your feet when you go outside. You may also want to avoid wearing bright clothes as well as lotions, perfumes, or other products that may attract insects.
• Avoid drinking out of open beverage containers when outdoors, since these can attract stinging insects.
• Tell your doctor and other healthcare professionals about any known medication allergies.

You can stay prepared for anaphylaxis by:

• Always carrying your epinephrine injector.
• Wearing a medical alert bracelet or necklace or carrying a card that notes your allergy.
• Explaining your allergy to friends, family, co-workers, and anyone else you spend a lot of time around. It's always a good idea to make sure they know the signs of anaphylaxis and how to use your epinephrine injector, in case you're unable to inject yourself.

Insider's takeaway

Anaphylaxis can be a life-threatening emergency, but with quick epinephrine treatment you can usually make a full recovery.

You can reduce your risk of anaphylaxis by staying away from known allergy triggers, like certain foods, medications, or insect stings.

It's always wise to tell people close to you that you've experienced anaphylaxis before. Explain how to use your epinephrine auto injector in case you have an anaphylactic reaction and need help.

If you or someone near you has symptoms of anaphylaxis, like difficulty breathing and swollen lips or face, immediately use an epinephrine auto injector, if available, and call 911.