Why do mosquito bites cause allergic reactions?
May 13, 2025
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
Mosquito bites引发过敏反应主要涉及免疫系统过度反应、蚊子唾液中的毒素与酶、组胺释放与血管扩张、皮肤屏障受损与感染风险、过敏体质的遗传倾向等。如果出现过敏反应，可以在医生指导下使用丹皮酚软膏、复方倍氯米松樟脑乳膏、樟脑薄荷柳酯乳膏等药物缓解症状。
Allergic reactions caused by mosquito bites mainly involve excessive immune system responses, toxins and enzymes in mosquito saliva, histamine release and vasodilation, compromised skin barrier and risk of infection, as well as genetic predispositions to allergies. If an allergic reaction occurs, medications such as paeonol ointment, compound beclomethasone and camphor cream, and camphor menthol salicylate cream may be used under a physician's guidance to alleviate symptoms.
The main reasons why mosquito bites can cause allergic reactions include excessive immune response, toxins and enzymes in mosquito saliva, histamine release and vasodilation, impaired skin barrier and risk of infection, and genetic predisposition to allergies. If any abnormalities occur, prompt medical attention is recommended. The detailed explanation is as follows:
1. Excessive immune response: The human immune system may have an excessive response to mosquito bites. This excessive reaction can not only cause local skin inflammation and itching but may also trigger systemic allergic reactions, such as difficulty breathing, fever, and general discomfort.
2. Toxins and enzymes in mosquito saliva: When mosquitoes bite, they inject saliva into the human body. The saliva contains various toxins and anticoagulant enzymes. These substances can inhibit blood coagulation in the human body, allowing the mosquito to suck blood smoothly. These toxins and enzymes may trigger immune responses in individuals with sensitive constitutions, leading to allergic symptoms.
3. Histamine release and vasodilation: After a mosquito bite, the human immune system identifies and attacks foreign substances in the mosquito's saliva, triggering a series of immune responses. These responses include the release of histamine, a substance that can cause vasodilation and inflammation. Vasodilation leads to symptoms such as redness, swelling, pain, and itching at the bite site.
4. Impaired skin barrier and risk of infection: When mosquitoes bite, their mouthparts pierce the skin, causing tiny wounds. These wounds not only disrupt the skin's natural barrier but also increase the risk of microbial invasion such as bacteria and viruses. Individuals with sensitive constitutions are more prone to allergic reactions when their skin barrier is compromised.
5. Genetic predisposition to allergies: Allergic constitutions often have a genetic predisposition. If there is a family history of allergic reactions to mosquito bites, the likelihood of an individual experiencing an allergic reaction after being bitten also increases.
If an allergic reaction occurs, medications such as peony phenol ointment, compound beclomethasone camphor cream, and camphor camphor salicylate cream can be used under a doctor's guidance to alleviate symptoms.
