Recommendations
Canadian allergists recommend the following six key points for dealing with anaphylaxis as stated in Anaphylaxis in Schools & Other Settings.
1. Epinephrine is the first line medication that should be used for the emergency management of a person having a potentially life-threatening allergic reaction.
In studies of individuals who have died as a result of anaphylaxis, epinephrine was underused, not used at all, or administration was delayed.1-4
The course of an anaphylactic episode cannot be predicted with certainty and may differ from one person to another and from one episode to another in the same person.5
It is recommended that epinephrine be given at the start of a known or suspected anaphylactic reaction.
Epinephrine should be injected in the muscle on the outer side of the thigh.
2. Antihistamines and asthma medications must not be used as first line treatment for an anaphylactic reaction.
While they will do no harm when given as additional or secondary medication, they have not been proven to stop an anaphylactic reaction.
Epinephrine is the only treatment shown to stop an anaphylactic reaction.
The main benefit of antihistamines is in treating hives or skin symptoms.
3. All individuals receiving emergency epinephrine must be transported to hospital immediately (ideally by ambulance) for evaluation and observation.
It is optimal to have patients transported to hospital by paramedics or local emergency medical services. While epinephrine is usually effective after one injection, the symptoms may recur and further injections may be required to control the reaction.
Repeat attacks have occurred hours later without additional exposure to the offending allergen.6,7 Therefore, it is recommended that a patient suffering from an anaphylactic reaction be observed in an emergency facility for an appropriate period because of the possibility of either a "bi-phasic" reaction (a second reaction) or a prolonged reaction8.
A four hour period of observation is advised, though this time may vary depending on the judgment of the attending physician who will take into consideration factors such as:
4. Additional epinephrine must be available during transport to hospital. A second dose of epinephrine may be administered within 5 to 15 minutes after the first dose is given IF symptoms have not improved.9,10
The second dose of epinephrine should only be given in situations where the allergic reaction is not under adequate control; that is, the reaction is continuing or getting worse.
Signs that the reaction is not under adequate control:
Optimally, patients should also have access to a back-up auto-injector in case a second dose of epinephrine is required.
It is important for persons at risk of anaphylaxis to take extra precautions when planning trips or camping outdoors. When travelling, they should try to be within a reasonable distance to a medical facility should an emergency occur.
5. Individuals with anaphylaxis who are feeling faint or dizzy because of impending shock should lie down, unless they are vomiting or experiencing severe respiratory distress.11
To improve blood circulation, caregivers should lift the person's legs above the level of the heart, keeping the legs raised by putting something (e.g. a pillow) underneath.
They should keep the person lying down until emergency responders arrive or until the patient has fully recovered.
If the person feels nauseated or is vomiting, lay the person on his or her side, head down, to prevent choking on vomit. (Note: if the person is having difficulty breathing, they should be sitting up.)
It is important that the patient not be made to sit or stand immediately following a reaction as this could result in another drop in blood pressure.11
Individuals at risk should be advised to seek help when experiencing an allergic reaction and to not go off alone (e.g. to the washroom) if they are feeling unwell. If they are alone and lose consciousness, no one will know they need help.
6. No person should be expected to be fully responsible for self-administration of an epinephrine auto-injector.
Individuals may not physically be able to self-administer epinephrine when they are suffering from a reaction.
They may be anxious about using a needle, may downplay the seriousness of a reaction, or may not want to draw attention to themselves. They may also be confused.
Assistance from others is crucial in these circumstances.
1. Epinephrine is the first line medication that should be used for the emergency management of a person having a potentially life-threatening allergic reaction.
In studies of individuals who have died as a result of anaphylaxis, epinephrine was underused, not used at all, or administration was delayed.1-4
The course of an anaphylactic episode cannot be predicted with certainty and may differ from one person to another and from one episode to another in the same person.5
It is recommended that epinephrine be given at the start of a known or suspected anaphylactic reaction.
Epinephrine should be injected in the muscle on the outer side of the thigh.
2. Antihistamines and asthma medications must not be used as first line treatment for an anaphylactic reaction.
While they will do no harm when given as additional or secondary medication, they have not been proven to stop an anaphylactic reaction.
Epinephrine is the only treatment shown to stop an anaphylactic reaction.
The main benefit of antihistamines is in treating hives or skin symptoms.
3. All individuals receiving emergency epinephrine must be transported to hospital immediately (ideally by ambulance) for evaluation and observation.
It is optimal to have patients transported to hospital by paramedics or local emergency medical services. While epinephrine is usually effective after one injection, the symptoms may recur and further injections may be required to control the reaction.
Repeat attacks have occurred hours later without additional exposure to the offending allergen.6,7 Therefore, it is recommended that a patient suffering from an anaphylactic reaction be observed in an emergency facility for an appropriate period because of the possibility of either a "bi-phasic" reaction (a second reaction) or a prolonged reaction8.
A four hour period of observation is advised, though this time may vary depending on the judgment of the attending physician who will take into consideration factors such as:
- the severity of the reaction
- the patient's response to treatment
- previous episodes
- distance from the hospital to the patient's home
4. Additional epinephrine must be available during transport to hospital. A second dose of epinephrine may be administered within 5 to 15 minutes after the first dose is given IF symptoms have not improved.9,10
The second dose of epinephrine should only be given in situations where the allergic reaction is not under adequate control; that is, the reaction is continuing or getting worse.
Signs that the reaction is not under adequate control:
- the patient's breathing becomes more difficult; or
- there is a decreased level of consciousness
Optimally, patients should also have access to a back-up auto-injector in case a second dose of epinephrine is required.
It is important for persons at risk of anaphylaxis to take extra precautions when planning trips or camping outdoors. When travelling, they should try to be within a reasonable distance to a medical facility should an emergency occur.
5. Individuals with anaphylaxis who are feeling faint or dizzy because of impending shock should lie down, unless they are vomiting or experiencing severe respiratory distress.11
To improve blood circulation, caregivers should lift the person's legs above the level of the heart, keeping the legs raised by putting something (e.g. a pillow) underneath.
They should keep the person lying down until emergency responders arrive or until the patient has fully recovered.
If the person feels nauseated or is vomiting, lay the person on his or her side, head down, to prevent choking on vomit. (Note: if the person is having difficulty breathing, they should be sitting up.)
It is important that the patient not be made to sit or stand immediately following a reaction as this could result in another drop in blood pressure.11
Individuals at risk should be advised to seek help when experiencing an allergic reaction and to not go off alone (e.g. to the washroom) if they are feeling unwell. If they are alone and lose consciousness, no one will know they need help.
6. No person should be expected to be fully responsible for self-administration of an epinephrine auto-injector.
Individuals may not physically be able to self-administer epinephrine when they are suffering from a reaction.
They may be anxious about using a needle, may downplay the seriousness of a reaction, or may not want to draw attention to themselves. They may also be confused.
Assistance from others is crucial in these circumstances.
- Pumphrey RSH. Lessons for management of anaphylaxis from a study of fatal reactions. Clinical Experimental Allergy 2000:30(8):1144-50.
- Yunginger JW, Sweeney KG, Sturner WQ, et al. Fatal food-induced anaphylaxis. Journal of the American Medical Association 1988;260(10):1450-2.
- Sampson HA. Mendelson L, Rosen JP. Fatal and near fatal reactions to food in children and adolescents. New England Journal of Medicine 1992; 327(6):380-4.
- Bock SA, Munoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. Journal of Allergy and Clinical Immunology 2001;107:191-3.
- Simons FER. First-aid treatment of anaphylaxis to food: Focus on epinephrine. Journal of Allergy and Clinical Immunology 2004;113:837-844.
- Stark BJ, Sullivan TJ. Biphasic and protracted anaphylaxis. Journal of Allergy and Clinical Immunology 1986;78:76-83.
- Lieberman P. Biphasic Anaphylaxis (Review). Allergy and Clinical Immunology International - Journal of the World Allergy Organization 2004;16:241-248.
- Sampson HA. Anaphylaxis and Emergency Treatment. Pediatrics 2003;111;1601-1608.
- Sicherer SH, Simons FE; American Academy of Pediatrics, Section on Allergy and Immunology, Self-injectable Epinephrine for First-Aid Management of Anaphylaxis. Pediatrics 2007; 119: 638-646
- Lieberman P. et al. The diagnosis and management of anaphylaxis: an updated practice parameter. Journal of Allergy and Clinical Immunology 2005;115:S483-523.
- Pumphrey RSH. Fatal posture in anaphylactic shock. Journal of Allergy and Clinical Immunology August 2003 (Letters to the Editor).
