Over-the-counter insect bite remedies not very effective

By Dr. Ananya Mandal, MDApr 12 2012

Many people go for over-the-counter remedies for insect bites. But the medicine could be simply a waste of both time and money.

Research suggests that most victims of home-bred midges, mosquitoes, flies, bedbugs and fleas will get better without any treatment at all. The review in the Drug and Therapeutics Bulletin (DTB), which offers impartial advice to doctors, admits that getting bitten may be horribly uncomfortable but there is little evidence that over-the-counter remedies work. Putting a cold compress to relieve pain and swelling could be a better option say researchers. Medical help should clearly be sought if serious symptoms, such as infections or anaphylactic shock, developed the DTB added.

Many preparations are available but few have been properly tested against bites. Because of their use in other areas, such as steroid cream to reduce itching from eczema, it has been assumed they would help treat bites, said the DTB.

Although on average each week GPs saw only five cases of insect bites per 100,000 patients, the problem was greater because people often consulted a pharmacist, used over-the-counter cures or did not seek treatment, the study said. Bites by mosquitoes, bedbugs and fleas are generally mild because they have “piercing mouthparts” that slice open the skin, and inject saliva containing anti-coagulant to keep the blood flowing, though itching and swelling follow. By contrast, horseflies, gnats and midges rip apart the skin more roughly and cause more painful wounds – which can cause dizziness, weakness and wheezing.

Antihistamine tablets, and steroid creams and tablets are widely recommended to calm itching but there is little evidence to back this up. The exception was people with eczema, added the bulletin. It said creams with painkillers or anesthetics are only ‘marginally effective’ but there is some evidence dilute ammonium solution may relieve itching or burning.

DTB deputy editor David Phizackerley said, “Our message is that most insect bites will clear up without treatment.” Sheila Kelly, chief executive of the industry body for over-the-counter products, said the ingredients were known to work against chemicals causing the symptoms.