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Allergic Reaction First Aid: What to Do

What is an allergic reaction?


  1. You can treat allergic reactions with antihistamines, decongestants, and hydrocortisone creams.
  2. Allergic reactions can vary from person to person and depend on the type of allergy.
  3. Go to the emergency room if you’re experiencing anaphylaxis, even if the symptoms get better.

Your immune system creates antibodies to fight off foreign substances so you
don’t get sick. Sometimes your system will identify a substance as harmful even
though it isn’t. When this happens, it’s called an allergic reaction.

These substances, or allergens, can be anything from food, medication, or environments.

When your body comes in contact with these allergens, it can cause mild
symptoms like skin irritation, watery eyes, or sneezing. In some people allergies
can cause anaphylaxis. Anaphylaxis is a life-threatening condition that will
cause shock, a sudden drop in blood pressure, and trouble with breathing. This
can lead to respiratory failure and cardiac arrest.

Call 911 immediately if you or someone you know is experiencing anaphylaxis.

What are the symptoms of an allergic reaction?

Your body’s allergic reaction depends on what you’re allergic to. Parts of
your body that will react include your:

  • airways
  • nose
  • skin
  • mouth
  • digestive system

Common symptoms

Take a look at the table below to see which symptoms commonly show up for
which allergy.

Environmental allergy Food allergy Insect sting allergy Drug allergy
Runny or stuffy nose
Skin irritation (itchy, red, peeling)
Trouble breathing
Nausea or vomiting
Short of breath, or wheezing
Watery and bloodshot eyes
Swelling around the face or contact area
Rapid pulse


Anaphylaxis or severe reactions

The most serious allergic reactions can cause anaphylaxis. This
reaction occurs minutes after exposure and, if left untreated, can
lead to loss of consciousness, respiratory distress, and cardiac arrest.

Signs include:

  • skin reactions such as hives, itching, or pale
  • wheezing or trouble with breathing
  • lightheadedness, dizziness, or fainting
  • facial swelling
  • nausea
  • weak and fast pulse

Get emergency help if you or someone you know is
experiencing anaphylaxis, even if symptoms start to improve. Sometimes symptoms
can return.

What to do when someone is experiencing anaphylaxis

If you’re with someone who is experiencing anaphylaxis, you should:

  • Call 911 immediately.
  • See if they have an epinephrine
    (adrenaline) auto injector and help them, if needed.
  • Try to keep the person calm.
  • Help the person lie on their back.
  • Raise their feet about 12 inches and cover them
    with a blanket.
  • Turn them on their side if they are vomiting or
  • Make sure their clothing is loose so they can

The sooner the person gets their epinephrine, the better. Avoid giving oral
medications, anything to drink, or lifting their head, especially if they’re
having trouble breathing.

After the first anaphylaxis experience, your doctor can prescribe emergency
epinephrine. The auto injector comes with a single dose of medication to inject
into your thigh. You’ll want to teach your family and close friends how to
inject the adrenaline in cause of an emergency.

CPR for anaphylaxis

If the person you’re with isn’t breathing, coughing, or moving, you may need
to perform CPR. This can be done even without formal CPR training. CPR involves
doing chest presses, about 100 per minute, until help arrives.

If you’re interested in learning CPR, contact the American Heart Association, American Red Cross, or a local first-aid
organization for training.

Learn how to perform hands-only and mouth-to-mouth CPR
here »

General treatments for allergic reactions

Over-the-counter (OTC) antihistamines and decongestants may relieve minor symptoms.
Antihistamines prevent symptoms such as hives by blocking histamines receptors
so your body doesn’t react to the allergens. Decongestants help clear your
nose, especially for seasonal allergies. But don’t take them for more than
three days.

These medications are available in tablets, eye drops, and nasal sprays. Many
OTC drugs also cause drowsiness, so avoid taking them before driving or doing
work that requires a lot of concentration.

Swelling, redness, and itching may be reduced with ice and
topical creams that contain corticosteroids.

Make an appointment with your doctor if OTC drugs don’t work.
Call the doctor right away if you have allergic reactions to the medication.

Pricing for allergy medication

Pricing of medications used to treat allergies | HealthGrove

Treatments for food allergies

The best remedies for food allergies usually entail avoiding
foods that trigger an allergic reaction. If you accidentally come in contact or
eat the food you’re allergic too, OTC drugs can temper the reaction. However,
these drugs only help relieve hives or itching. Oral cromolyn,
which is only available by prescription, can help your other symptoms.

You may also treat severe food allergies with epinephrine.

Pricing for food allergy medication

Pricing of medications used to treat food allergies | HealthGrove

Treatments for plant or bite allergies


According to The
Children’s Hospital of Philadelphia, about seven out of 10 people have an
allergic reaction when they touch poison ivy, poison oak, and poison sumac. The
sticky substances from these plants, also called urushiol, bind to the skin
upon contact.

Symptoms range from mild redness and itching to severe blisters and swelling.
Rashes appear anywhere from three hours to a few days after contact and last one
to three weeks.

If exposed to poisonous plants, you should:

  • Avoid touching other areas of your body,
    especially your face.
  • Clean the area with soap and water for at least
    10 minutes.
  • Take a cool bath.
  • Apply calamine, or anti-itching, lotion three to
    four times a day to relieve itching.
  • Soothe inflamed areas with oatmeal products or
    one percent hydrocortisone cream.
  • Wash all clothing and shoes in hot water daily.

These steps all focus on removing the urushiol from your skin. Severe
reactions in children may require a doctor’s visit to prescribe oral steroids or
stronger creams to ease the symptoms.

You should see a doctor if you have a high temperature and:

  • the scratching gets worse
  • the rash spreads to sensitive areas like the
    eyes or mouth
  • the rash doesn’t improve
  • the rash is tender or has pus and yellow scabs

Despite claims, there’s no scientific evidence to support that
scratching an open wound leads to poison in the bloodstream. The left over
oil would only touch the immediate area. Avoid spreading the oil immediately by
washing the affected area with soap and water.


Most people will have a reaction to an insect bite, but the most serious
reaction is an allergic one. About 2 million people in the United States are
allergic to insect stings, according to the Cleveland

Most common insect stings are from:

  • bees
  • wasps
  • yellow jackets
  • hornets
  • fire ants

Treat insect allergies by:

  • removing the stinger with a straight edge object,
    such as a credit card, and using a brushing motion (pulling or squeezing a
    stinger may release more venom into your body)
  • washing the area with soap and water and
    applying an antiseptic after
  • applying hydrocortisone cream or calamine lotion
    and covering the area with a bandage
  • applying a cold compress to the area, if there’s
  • taking antihistamine to reduce itching,
    swelling, and hives
  • taking aspirin to relieve pain

Children and pregnant women shouldn’t take OTC medication as there may be
unintended side effects like Reye’s syndrome, which is a rare but serious liver
and brain disorder.


If a jellyfish stings you, wash the area with seawater or vinegar for 30
minutes. This will neutralize the jellyfish’s toxin. Apply something cold on
the affected area to soothe your skin and lessen pain. Use hydrocortisone cream
and antihistamine to reduce swelling.

British Red Cross advises that urinating on a jellyfish sting won’t
help. In fact, it may actually increase pain.

Treatment for drug allergies

In most drug allergy cases, your doctor should be able to
prescribe an alternative medication. Antihistamines, corticosteroids, or
epinephrine may be needed for more serious reactions.

Otherwise, your doctor may recommend a desensitization procedure.
This means taking small doses of the medication until your body can handle your

How to prevent allergic reactions

Once you’ve had an allergic reaction, it’s important to identify the source to
avoid future contact. For ingredient-specific allergies, check product ingredients
before purchase. Applying lotion before going hiking or camping may help to
prevent poison ivy from spreading or absorbing into your skin.

The more control you keep over your contact with allergens, the less likely you’ll
have an allergic reaction. Make sure your coworkers and friends know about your
allergies and where you keep your epinephrine auto injector. Teaching your
friends how to treat an allergic reaction can help save a life.

Posted by: Dr.Health

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