Anaphylaxis describes a severe allergic reaction. It can result in a potentially fatal state known as anaphylactic shock.
Common substances to which the body responds include food, bites of insects, poison, and medicine. These are known as allergens.
According to Food Allergy Research and Education (FARE), food allergy is the principal cause of anaphylaxis outside of the hospital.
Anaphylactic reaction to food is responsible for one emergency department visit in the United States (U.S.) every 3 minutes, mostly in adolescents and young adults.
Medications, foods, and insect stings are the most common triggers.
Fast facts about anaphylaxis
- Anaphylaxis is a severe allergic reaction.
- It can cause breathing problems, plummeting blood pressure, shock, and potentially death.
- Anaphylactic reactions to allergens in food cause one hospital visit every 3 minutes in the U.S.
- An adrenalin shot, such as from an EpiPen, can help to stop the progression of symptoms.
- Avoiding known allergens can reduce the risk of anaphylaxis. However, if an allergen has never caused reaction before, there is no way to prepare for its anaphylactic reaction.
What happens in anaphylaxis?
Many people, with watery eyes, a runny nose, and perhaps a rash, react to a drug, or allergen. A severe allergic reaction may however lead to a serious condition known because anaphylaxis.
Anaphylaxis happens when the body is reacting badly to a substance, or allergens, as if it were a health threat, such as bacteria or virus.
The body produces large quantities of histamine which triggers an inflammatory response.
This reaction may lead to blood vessel dilation, a sudden drop in blood pressure, loss of consciousness and shock. Breathing is tricky as the airways close. The blood vessels may leak into surrounding tissue, resulting in edema, or swelling.
The reaction can occur at once, within hours, or very rarely a few days after the allergens come into contact.
Symptoms
Understanding the signs and symptoms of anaphylaxis is significant, because immediate action may be required.
They include:
- difficulty breathing, wheezing, shortness of breath, tightness in the throat and chest pain
- trouble swallowing
- a cough and a hoarse voice
- itchy mouth or throat and nasal congestion
- feeling that something is stuck to the tongue, or in the throat
- a full and heavy feeling in the tongue
- swelling and itchiness on the skin, with hives, warmth, redness, and a rash
- stomach pain and cramps, with nausea, vomiting, and diarrhea
- anxiety and a feeling of impending doom
- swelling of the feet, hands, lips, eyes, and sometimes the genitals
- low blood pressure and poor circulation leading to pale blue skin, a low pulse, dizziness, or faintness
- shock
- loss of consciousness
The person also may have itchy, swollen, watery eyes, a headache, and uterine cramping. They could have a metallic taste in their mouths.
Extreme difficulty in breathing, a extreme drop in blood pressure, or both can lead to shock, and this can be fatal.
First aid
If a person begins to develop serious allergic symptoms, urgent medical treatment is needed.
First aid for anaphylaxis includes:
- removing the allergen, if possible, and calling for emergency assistance
- finding out if the patient has a history of allergy
- helping them administer any medication they may have
- reassure the patient so that they feel comfortable
If the patient knows they’re allergic, they may have medicine that they can use in the form of an adrenalin injection kit, such as an EpiPen.
The injector is to provide a dose of epinephrine, an adrenaline source.
Breathing
The person who is with the patient will ensure they can breathe while waiting for help.
The person should stay sitting up to make breathing easier, but if there is a decrease in blood pressure they should be put flat on the ground with their legs extended.
If they become weak, somebody should make sure that they can breathe. These can be placed in the role of recovery.
Anyone who’s living with the patient should monitor their condition.
When a health care provider visits, when possible be ready to tell them:
- what caused the reaction
- whether the person experiencing anaphylaxis has self-medicated
Keep a sample of the element that triggered the reaction if necessary, and have it follow the patient to the hospital;
The cardiopulmonary resuscitation (CPR) should be conducted and continued until the rescue team arrives, should the breathing stop completely.
Treatment
An epinephrine, or adrenaline, injection will be the immediate aid for a patient with serious anaphylaxis.
Adrenaline, also known as epinephrine, acts in various ways.
- It causes the blood vessels to constrict, and this decreases swelling and helps increase blood pressure.
- It helps relax the muscles around the lung.
- It prevents the release of additional allergic chemicals.
This helps to halt further progress in the reaction.
Most patients respond to this treatment well, and at this stage, symptoms usually begin to subside. If there is no change then after 10 minutes the patient should receive another dose.
Sometimes, after taking adrenalin, symptoms subside, but then return. The patient may be held in hospital for 24 hours under observation.
The doctor can give corticosteroid or antihistaminic injections for a less severe reaction.
Prevention
Anaphylaxis is an emergency which is life threatening. Those with allergies are the ones most vulnerable to that.
This isn’t always straightforward though. Some people react to a material which hasn’t previously affected them.
The individual should remember what triggered it after having an allergic reaction, and try to avoid that in the future.
Since it is not always possible to avoid an allergen, they may need to bring an injector and wear a bracelet to let others know they have an allergy People should let their families, employers or school staff know about any allergies that could trigger a severe reaction.
Anaphylaxis is a life-threatening emergency which needs immediate support. Everyone should know the symptoms and signs, and how to respond.
