Mosquito Bites

Mosquito bites are a fact of summer. The typical reaction is immediate swelling at the site of the bite followed by redness about twenty minutes later. A firm itchy nodule develops over the next 24 to 36 hours and will last about 7-10 days.

People who have never been exposed to a particular species of mosquitos don’t develop reactions to the initial bites. Subsequent bites result in the appearance of delayed local skin reactions. After repeated bites, immediate swelling occurs. With further exposure, the delayed local reactions wane and eventually disappear, although the immediate reactions persist. People who are repeatedly exposed to bites from the same species of mosquito eventually also lose their immediate reactions. The duration of each of these five different stages differs, depending on the intensity and timing of mosquito exposure.

Large local reactions to mosquito bites have been named the Skeeter Syndrome. Large local reactions develop within hours of the bite, progress over 8 to 12 hours or more, and resolve within 3 to 10 days. The area can blister and looked bruised. Severe large local reactions can be accompanied by low- grade fever and malaise. It can be difficult to differentiate between allergic inflammation caused by mosquito bites and inflammation caused by secondary bacterial infection after scratching the bites. Large local reactions typically begin within hours. Secondary bacterial infections typically begin within days.

The goal of treatment of local reactions to mosquito bites is to reduce symptoms. The first line of therapy is a non-sedating antihistamine such as certirizine (Zyrtec). A topical steroid cream can be very helpful to reduce itching and swelling; prescription products are more powerful and may be more effective. If the bite causes eye swelling that interferes with vision, lip swelling that interferes with eating or drinking or it’s difficult to use a limb, oral steroids can be used.

Prevention is the best medicine! Cover up, avoid going out at dawn and dusk and avoid wetlands, tall grass and brush. Insect repellents are appropriate for emergency use.