Allergic reactions to fleas typically occur from contact with the anti-coagulant that the flea injects into the bite, or to other animals bitten by the flea in the past. Signs of an allergic reaction to fleas may be a more severe bite, a red rash at the site, or in severe cases, hives and swelling. Bites are located in clusters and may be a white or red bump. Prevention means treating the source of the fleas, and alleviating the itching until the bite heals.
Most people will not see just one bite, but several in clusters. Usually bites are located near where elastic bands rest on the body, such as around socks and underwear. The bite will appear as a a slightly raised bump, with either a white or red tone. There are several insect bites that look like a bite from a flea, but are actually from another bug such as bed bugs and flies.
An allergic reaction to fleas is usually not an allergy to the flea itself, but to chemicals in its saliva, which act as an anti-coagulant to blood flow. In addition, people with allergies to dogs or cats may have a reaction to the dog or cat that was bitten in the past by the same flea. Most likely, allergic reactions will appear as just a larger, itchier bite.
There are other types of allergic reactions than the more severe bite site. Another sign is a red rash at the area around the bite. Extreme allergies appear after the bite with hives and swelling.
Preventing an allergic reaction to fleas involves treating the source. Fleas rarely feed on a human as an initial host, so pets should be checked and treated by a veterinarian. Various methods of treating pets with fleas are available. Extended time outdoors or exposure to other animals may also be the culprit. Fleas can live a long time without feeding, so household items will need treatment once an infestation is known.
Once bites are discovered, treating an allergic reaction to fleas becomes a priority. The bite and the area around it should be washed with water and antibacterial soap. Cold compresses can be applied to reduce itching, as well as topical creams and oral antihistamines. Scratching will lead to the wound opening and possibly an infection, so it should be avoided. Healing generally takes about one week, but may take up to three.