Allergic reaction to a mosquito bite
A small local skin reaction to a mosquito bite is normal and does not count as an allergic reaction.
For this, the skin swelling must reach a diameter of over 10 cm and persist for at least 24 hours. The swelling often heals slowly and residues, such as small scars, can remain at the site of the puncture. In addition, other symptoms can occur. This depends on the severity of the allergic reaction.
Symptoms of an allergic reaction to a mosquito bite
An allergic reaction to a mosquito bite can have different degrees of severity.
- Grade 1 includes the local skin reaction, which is associated with redness and itching. The swelling can have a diameter of over 10cm.
- In severity grade 2, nausea and anxiety are added to the local symptoms.
- These symptoms can escalate to vomiting and nausea. Then one speaks of grade 3.
- If there are shortness of breath and difficulty swallowing, a severity grade 4 is assumed. The patients can already suffer from fear of death here.
- The last degree of severity is allergic shock. This can lead to a circulatory breakdown and is always to be assessed as life-threatening.
Learn more at:
- Allergic Reaction - You Should Know That!
- How do you recognize an allergy to a mosquito bite?
Swelling from an allergic reaction to a mosquito bite
The swelling of the puncture site is one of the classic symptoms of a mosquito bite.
From a diameter of 10 cm, one speaks of an allergic reaction to the insect. The swelling then resembles the one you get from stings by wasps or bees. The swelling can also be painful. All diameters smaller than 10 cm are normal skin reactions that also occur in non-allergy sufferers.
The swelling can also escalate into hives. Here wheals are characteristic. Wheals are point- to plateau-shaped elevations on the skin. There may also be swelling of the face. Then one speaks of an angioedema (Quincke's edema). Angioedema is Grade 3.
Please also read the general topic: Swelling after a mosquito bite
Itching from an allergic reaction to a mosquito bite
The itching is caused by the irritation of slowly conducting nerve fibers by various hormones. These nerve fibers are normally responsible for transmitting pain stimuli. It is important not to scratch as much as possible despite the itching. This only distributes the mosquito's saliva and only expands the defense reaction and ultimately also the itching.
In addition, scratching can damage the surface of the skin and the mosquito bite becomes infected.
Read on under: Inflammation after a mosquito bite
What to do if you have an allergic reaction to a mosquito bite
A mosquito bite that does not swell exceptionally strong does not necessarily require therapy. Local cooling can often help against the usually troublesome itching. The cooling can be done either with cold water or cooling gels or ointments.
If the mosquito bites swell or if the itching prevents you from falling asleep, an antiallergic agent can be taken. These are available from the pharmacy without a prescription. Before using it for the first time, you should seek advice from a doctor or pharmacist which preparation is best to take and in which dosage.
Histamine blockers may also have to be taken if the symptoms are appropriate. In this case, however, a doctor should first be consulted, as these drugs must not be taken for a long period of time.
If a mosquito bite is scratched on, bacteria can accumulate there and trigger an infection. In some cases an antibiotic is necessary.
You can also find out more at: Immediate action in the event of an insect bite
Does calcium help against an allergic reaction after a mosquito bite?
Calcium has no relieving or prophylactic effect in the event of an allergic reaction to a mosquito bite or any other allergies.
The antiallergenic effect of calcium used to be a hot topic, but today it can definitely be said that it plays no role in allergies and can even have negative effects. There are also no scientifically serious studies that investigate the connection between allergies and calcium.
You may also be interested in this topic: Therapy for an allergy
Home remedies for allergic reactions to a mosquito bite
With mosquito bites, the itching is particularly stressful. This is caused by the body's defense reaction to the mosquito's saliva. The most important measure is therefore not to spread the mosquito's saliva further by scratching it.
The itching can be relieved with cooling. Cold water is suitable for this. If sufficient cooling cannot be achieved in this way, you can also use an ice cube or a cooling element. For example, a kitchen towel should be placed on the skin as a protective layer so that the cold does not cause skin lesions.
Alternatively, a halved onion, a potato and a slice of lemon can be held on the mosquito bite to reduce the itching. The same effect is achieved by placing fresh leaves of the ribwort. The leaves can be wrapped around the skin with a compress. They can stay there for up to two hours.
The juice of the aloe vera plant is also said to have an itch-relieving effect. Simply apply this to the affected area and let it take effect. A few drops of tea tree oil also have a cooling effect and prevent infection.
Further information on the topic can be found here: Home remedies for mosquito bites
Causes of an allergic reaction to a mosquito bite
If a mosquito bites an area of skin, it distributes a small amount of its saliva there. The mosquito's saliva inhibits the coagulation system at this point. This is necessary so that the mosquito can suck off blood without it first clumping through the human coagulation system.
The body perceives the sting and the injection of saliva as a disorder and triggers a cascade of defense mechanisms. The hormone histamine is also released as part of these mechanisms. Histamine is a messenger substance and plays a role in allergic and inflammatory reactions. The blood vessels widen in the affected area so that many substances can get there as quickly as possible. This is the cause of the redness.
Due to the enlarged vessels, however, fluid is also stored in the tissue and this leads to the well-known swelling after a mosquito bite. The itching is triggered by the irritation of so-called C-fibers. The C-fibers are slowly conducting nerve fibers. They are especially responsible for the perception of pain.
You might also be interested in this topic: Allergy to bee venom
Diagnosis of an allergic reaction to a mosquito bite
First, a doctor will discuss whether it is really an allergic reaction to a mosquito bite or whether another insect allergy could be present. Then the individual symptoms are dealt with. The symptoms that go beyond the usual skin reaction are particularly important for the doctor.
Then the doctor can also carry out a so-called provocation. In a controlled environment, a little of the mosquito saliva is applied to an area of skin and brought into the skin with a lancet. The reaction to this allergen is then observed. In addition, antibodies can also be detected in the blood. These tests should be carried out shortly after the insect bite and then again a few weeks later.
Read more about this:
- Allergy diagnostics
- Prick test
Duration of an allergic reaction to a mosquito bite
By definition, an allergic reaction to a mosquito bite lasts at least 24 hours. The skin reactions usually heal within a few days. The exact duration depends on the severity of the rash. The use of antiallergic drugs can also have a positive effect in the long run.
So that it doesn't get that far, you should pay attention to mosquito repellent, especially if you tend to have allergic reactions quickly.
Find out more at: Mosquito repellent
Course of disease
The first reactions can be seen within seconds. Since the allergy to mosquito bites is an allergy of the immediate type, all other symptoms develop very quickly, usually within 30 minutes. If swellings develop on the face or neck with shortness of breath shortly after a mosquito bite, a doctor should be consulted as soon as possible.
Allergic reaction to a mosquito bite in the child
In children, an allergic reaction to a mosquito bite can quickly show pronounced symptoms.
They show symptoms similar to those of adults. With pronounced allergies, nausea, vomiting and severe palpitations may occur. However, children do not have as many reserves as adults, so an allergic reaction must always be taken first.
In the worst case, a mosquito bite can trigger an anaphylactic reaction. This can then be accompanied by shortness of breath and circulatory problems. If in doubt, a doctor should be consulted early, as life-threatening conditions can quickly develop in children. It is therefore recommended that children be desensitized if they have an allergy to mosquito bites. A small dose of the allergen is injected under the skin at regular intervals. This is supposed to help reprogram the immune system so that no excessive immune reaction is triggered.
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