An allergy is hypersensitivity to a substance (allergen) that is normally considered to be harmful. Allergies are triggered by the immune system, which reacts to the allergen as though it were a harmful substance invading the body. The most extreme response is anaphylactic shock which, if untreated, can kill.
CAUSES OF ANAPHYLAXIS
 This extreme allergic reaction has an intense effect on the body, causing a sudden drop in blood pressure and narrowing of the airways that can be fatal. Anaphylactic shock can be caused by anything but among the most common triggers are: nuts (for those who are particularly sensitive, even touching the trace of a nut can be potentially fatal), seafood, insect stings and bites, and drugs (some people have very extreme reaction to penicillin, for example).
As with asthma, the number of people suffering allergic reactions appears to be increasing. Whether this is because people are becoming more sensitive to allergens (the substances that cause allergic reactions) or whether we are just becoming better at detecting allergies, nobody is really sure.
SIGNS AND SYMPTOMS
One of the main effects of severe anaphylaxis is a constrictions of the air passages in a similar way to asthma but generally more severe, preventing the intake of any oxygen at all. There may be a history of contact with a particular allergen, the thing that triggers the attack. Anaphylaxis can happen very quickly, within seconds.
Signs and symptoms include:
- Difficulty breathing
- Pale skin and blue lips
- Blotches on the skin
- Rapid pulse
- Breathing and heartbeat stopping
TREATMENT
- Call an ambulance immediately. The victim needs epinephrine to counteract the reaction.
- If the victim is a known sufferer she may have an epinephrine injection. Help her to administer this. If you have been trained and the victim is unable to do so, you may give the injection.
- Place the victim in the most comfortable position reassure her.
- If the victim becomes unconscious, place in the recovery position. Monitor the victim’s breathing and circulation and be prepared to resuscitate if necessary.
SKIN PRICK TEST FOR ALLERGIES
Skin prick tests are simple procedures carried out to find out what substances (allergens) cause allergic reactions in an affected person. Extracts of allergens that commonly cause allergic reactions, such as food, pollen, and dust are made into dilute solutions and are then placed on the skin. The skin is pierced to allow the substance to be absorbed.
- Dilute solutions of the substances that a person is thought to be allergic to are placed on the skin, usually the arm, and the skin is then pricked with a needle. Several different allergens can be tested on the skin at the same time.
- An allergic reaction usually takes place within 30 minutes of the test. If the person is allergic to the substance a red weal, indicating a positive reaction, appears at the site where the needle pricked the skin.
HANDLING AN ATTACK
Many anaphylaxis sufferers carry an auto-injector with a measured dose of a known treatment for an attack, most commonly epinephrine. This will often look like a pen. It is easily administered by placing against the skin and clicking the end. Help the person having the attack to find and inject the medication. |
