What is important to know about insect sting allergies

Severe allergy to insect stings is a problem affecting so many people. Significantly complicates the fight against it is that the body's high sensitivity to bites usually persists for life, and in many cases, allergy manifestations can intensify from one bite to the next.

Often a person has a hereditary predisposition to allergies. The unfavorable ecological situation, the ever-growing isolation of a person (especially a child) from nature, as well as some diseases increase this heightened sensitivity to various substances, thereby increasing the likelihood of a severe allergic reaction to a bite of almost any insect.

On a note

Poisons, saliva and other insect secretions are considered strong allergens. Sometimes even airborne chitinous hairs, pieces of external integument and insect excrement can cause a dangerous allergic reaction.

However, most often, cases of the most severe allergies are observed after bites from hymenoptera insects. In 7% of cases, these are bees, somewhat less often - wasps, hornets, bumblebees and tropical ants. Much less often, the body reacts heavily to the bites of mosquitoes, midges, fleas, bedbugs and other non-stinging insects.

The photo shows an example of a severe allergic reaction to a hornet sting:

The aggressive effect of the poison of Hymenoptera insects is due to the characteristics of its constituent components. So, for example, bee venom contains the following substances:

• Melitin - this compound actively destroys red blood cells, causes acute inflammation, muscle spasm and disruption of tissue metabolism, reduces blood clotting.
• Apamin - this protein has a significant similarity with the neurotoxins of snake and scorpion venoms, strongly excites the structures of the nervous system.
• Hyaluronidase - helps the poison spread throughout the body.
• Phospholipase A - enhances the inflammatory process and stimulates hemolysis of red blood cells.
• Histamine - dilates blood vessels, provokes inflammation.

In addition, a special protein included in bee venom causes mast cells in affected tissues to release their own histamine, which is the main activator of allergic processes.

The wasp venom is distinguished by the presence of the substance kinin, which causes vasodilation, contraction of smooth muscles and provokes acute inflammation. And the poison of various types of hornets also contains acetylcholine, which slows down the heart rate, lowers blood pressure, reduces the muscles of the bronchi and increases the secretion of the bronchial glands.

On a note

All over the world, three times more people die from allergic reactions to insect bites than from snake bites, and a person can die from a single bite.

The reaction to the bites of blood-sucking insects - bedbugs, fleas, mosquitoes, etc. - is due to the presence in their saliva of special enzymes that cause allergies (for example, substances that prevent rapid blood clotting). In addition, a flea, for example, often literally bites into the skin almost with its head, introducing additional irritating substances into the wound.

The photo below shows a flea at the time of the bite:

The saliva of adult bed bugs contains an analgesic, as a result of which their bites are practically painless and are usually detected only in the morning. Also, in the saliva of blood-sucking insects, pathogens of very dangerous diseases are sometimes present: malaria, plague, tularemia, hepatitis B, anthrax and others.

 

Symptoms and forms of an allergic reaction to insect bites

The strength of the allergic reaction of the body depends on the amount and degree of aggressiveness of the injected allergen, as well as on the amount of antibodies corresponding to it, circulating in the human blood. From bite to bite by insects of the same species, the antibody titer (that is, their concentration) may increase. Accordingly, the strength of the response of the body will also increase.

After an insect bite, an allergic reaction sometimes occurs instantly, and sometimes it manifests itself only for several tens of minutes, occasionally for hours. If there is no sensitization to the allergen, then the skin in the area of ​​damage turns red, swells, and itches. These symptoms usually do not last long and disappear without a trace. But in the presence of sensitization, the body reacts much more strongly, and such a reaction is no longer limited to local manifestations.

Photo of an allergic reaction to a bee sting:

Thus, the symptoms of an allergy to insect stings can vary greatly in nature and severity. For example, symptoms may be:

• Local - burning pain, swelling of the skin, swelling or induration, hyperemia, itching, rashes;
• Generalized - urticaria, conjunctivitis, rhinitis, weakness, fever with or without chills, dizziness, shortness of breath, lowering blood pressure, frequent pulse of weak filling, heart pain, fainting.

Life-threatening conditions such as Quincke's edema and anaphylactic shock can also be observed.

The photo shows an example of angioedema:

A rash from insect bites can also vary significantly in intensity, appearance, and localization. It can present with blisters, nodules, erythematous patches, erosions, and other variations. In difficult cases, a hemorrhagic, bullous, necrotic rash occurs.

When scratching through damaged skin, an infection can penetrate. In this case, the skin elements are converted into pustules (pustules), and sometimes into ulcers that do not heal for a long time.

Allergies from insect bites can be masked by other allergic reactions, as skin rashes can be similar. Therefore, in each case, you need to try to find out what exactly caused the rash.



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Allergy in a child: how dangerous is it?

Children often react to an allergen more strongly and for a longer period of time than adults (although in some cases the opposite is true).Spots from insect bites can persist for several days.

Often, insect bites are very itchy: due to constant itching, the child sometimes scratches the skin until it bleeds with the risk of infection, which can pose an additional health hazard.

Review

“We had a bad situation last summer. We got out to the Crimea for a week, to Olenevka, and there Sashenka was bitten by some kind of wasp. She says big and thin. I thought that he was fooling around, because in general he is a calm boy and even if he hurts, he will not yell. Immediately, he turned blue from screaming, we could not restrain him, there was an impression that he had some kind of convulsions. A terrible sight. His arm was swollen immediately, and so that he could not bend it. A rash appeared, and the face also spread to the back. And the child is still waving his hands and screaming. Okay, the infirmary was open. We drove him for the time being - about twenty minutes, probably, had passed, he had already fainted, his temperature had risen. The doctors injected something, put a dropper, said that the child had anaphylactic shock, and if we had been delayed, we might not have taken him. I later found out what kind of wasps they were. They say the roadies are called, brown and big, and their bite is the most painful. As a result, we were forced to stay in Crimea for another week, because Sasha was released from the first-aid post only five days later.

Ilona, ​​Voronezh

The photo below shows an example of severe irritation from insect bites in a child:

With high sensitization to hymenoptera venom, after a bite, a child can quickly develop a complicated reaction in the form of angioedema and anaphylactic shock.Parents of the baby should always keep this point in mind: if hives or other pronounced skin manifestations appear after an insect bite, as well as if general allergy symptoms occur, you should urgently consult a doctor. In this case, it is better not to self-medicate, because many drugs have restrictions for use in childhood.

 

What is the danger of an acute form of allergy?

Urticaria that occurs after insect bites is not the most severe variant of allergy manifestation. Much more dangerous are the symptoms of general intoxication, a sharp drop in blood pressure, suffocation and collapse - all this can pose a threat to human life.

The most dangerous complications of allergies are anaphylactic shock and Quincke's edema.

Quincke's edema, or, otherwise, giant urticaria, is an acute, extensive swelling of tissues with well-developed subcutaneous fat. Such edema is due to a powerful release of biologically active substances into the blood, which cause vasodilation and increase their permeability.

Severe swelling of the larynx and tongue is very dangerous - in this case, the risk of developing asphyxia is high, while a person may die from suffocation. Also, cerebral edema poses a high danger, as a result of which neurological symptoms may occur: convulsions and paralysis. With these severe reactions to insect bites, the patient should be urgently hospitalized for the treatment of allergies.

The photo below shows angioedema:

Anaphylactic shock, sometimes also developing after insect bites, occurs due to a violation of the peripheral and central circulation under the influence of biologically active substances that are released into the blood in large quantities (in particular, serotonin).

The victim becomes restless. He develops shortness of breath, impaired urination, confusion occurs. The skin becomes cold, cyanotic and moist. Nausea, vomiting, diarrhea can join.

In the case of developing anaphylactic shock, skin irritation that occurs after an insect bite is usually pronounced, accompanied by severe pain and increasing swelling. Local itching quickly spreads over a wide area of ​​the body. Often, laryngeal edema, broncho- and laryngospasm join, blood pressure drops. Without adequate treatment, a person can die within minutes or hours from suffocation and subsequent vascular collapse.

 

Antiallergic drugs for insect bites

Antiallergic drugs used after insect bites can be divided into the following groups:

• Antihistamines or, otherwise, H1-receptor blockers: I-th generation - Diphenhydramine, Diprazine, Suprastin, Tavegil, Diazolin, II-th generation - Astemizol, Terfenadine, III-rd generation - Loratadin (Claritin), Azelastine.
• Mast cell stabilizers: Nedocromil, Ketotifen, Intal.
• Glucocorticoids: Prednisolone, Hydrocortisone, Betamethasone.
• Symptomatic means: adrenaline, Salbutamol, Fenoterol.

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Of the antihistamines for insect bites, new generation drugs (II and III) are more often prescribed today. They do not have cardiotoxic and hepatotoxic effects, do not depress the central nervous system, the duration of their action is longer.

Widespread use for allergies, including insect bites, received Claritin. However, it is worth noting that in some cases it is justified to prescribe first-generation drugs that do not last long, but their action comes faster.

Important:

When taking any medications, including Diazolin, Suprastin, Dimedrol, etc., it must be remembered that the medicinal substances themselves can in rare cases cause allergic reactions, up to Quincke's edema.

In folk medicine, to relieve irritation that occurs after insect bites, calendula tincture, onion, plantain and lemon juice, as well as a solution of baking soda, are used. From mosquito bites, tincture of laconos, wood lice herb are used.

Essential oils of clove, anise, eucalyptus and basil repel insects.

Local inflammation relief from insect bites will be facilitated by hydrocortisone and other glucocorticosteroids used topically, for example, in the form of an ointment.

 

First aid for the development of an allergy to an insect bite

When bitten by stinging insects (wasps, hornets, bees), you should immediately provide first aid to a person, without waiting for signs of an allergy to appear.

Sometimes it seems to the victim that nothing terrible has happened - just think, a wasp (or a bee) has bitten. And most of the time, nothing really bad happens. However, sometimes an allergic reaction develops so rapidly that it can take minutes to count.

When a bee stings, it is necessary to remove the stinger with tweezers as quickly as possible, since the poison sac associated with it continues to contract and inject poison under the skin. In the case of wasp and hornet stings, you should not look for a sting - these insects do not leave it in the wound and can sting repeatedly.

No later than 1 minute from the moment of the bite, suction of the poison from the wound can be effective (this should be done for a short time, also no more than 1 minute, be sure to spit).

Then you need to slow down the rate of absorption of the poison into the blood, and also help reduce local allergic edema from an insect bite. To do this, you need to apply cold, for example, an ice pack, to the bite site.

If a person is prone to severe allergies to insect bites, knows about it, but it so happens that he does not have an adrenaline autoinjector with him (usually allergy sufferers always carry it with them), then it will be useful to take additional measures. When bitten in the leg or arm, a tourniquet is applied to the limb - this will buy time, and the poison will not be able to spread through the body with the bloodstream. An ambulance is urgently called.

Itching and rash after an insect bite help to reduce special preparations: these can be sprays and ointments containing panthenol, Fenistil gel, hormonal ointments such as Advantan and Hydrocortisone, special insect bite balms for children from the Gardex and Mosquitall series.

When providing first aid, you should not:

• Drink alcohol - to avoid vasodilation and accelerate the absorption of poison into the blood.
• Cool the bitten area with damp earth or clay - this way you can introduce an infection, including contracting life-threatening tetanus.
• Trying to squeeze poison out of the wound - such a massage will only provoke an accelerated spread of the poison into neighboring tissues.
• Use Diprazine and other first-generation H1-histamine blockers for severe allergic reactions. They are ineffective in relation to histamine, but at the same time they can dramatically lower blood pressure, which will further aggravate the situation.

 

What to do with serious consequences?

Complicated allergic reactions should be treated by a doctor.

At the prehospital stage, for the treatment of acute stenosis of the larynx, normalization of blood pressure, inhalations of glucocorticosteroids are used through a nebulizer (0.25 mg of Budesonide with a compensated stage of stenosis, 0.5 mg with subcompensated, 1 mg with grade III laryngeal stenosis). The maximum number of inhalations is 3 with an interval of 20 minutes.

Suprastin for complications after insect bites is used when inhalation therapy is ineffective or in the absence of a nebulizer - intramuscularly or orally (with compensated stenosis). Systemic glucocorticoids (prednisolone) are administered intravenously, adrenaline subcutaneously.

To relieve an asthma attack, you can use Berodual, Salbutamol - through an inhaler or nebulizer.

It must be remembered that when the first signs of a severe form of allergy appear after an insect bite, the victim must be taken to the hospital as soon as possible (you should also consult on the phone how to help the person). If others do not have experience in providing first aid, the victim should be put on his back, putting a roller of clothes under his head, provided with a drink and not given medicines, in which there is no full confidence.In many cases of acute allergies, it is the unprofessional actions of volunteers that contribute to the aggravation of the situation, and therefore the best thing to do is to get the person to the doctor as soon as possible.

 

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