Q. I have found vitamin B1 to be an effective deterrent for mosquito bites. I was recently in an area where I got multiple mosquito bites daily that itched unbearably. I developed open sores from scratching in my sleep, even when I used Benadryl or hydrocortisone cream.
In less than a week of taking vitamin B1 (500 mg per day), I have not had any more bites. I know there are studies that say vitamin B1 has no value for deterring insect bites, but my experience convinces me otherwise.

A. Thank you for sharing your testimonial. Some other readers have also found taking vitamin B1 (thiamine) helpful against mosquitoes. The research we have found, however, indicates that this vitamin is not effective as a systemic mosquito repellent (Journal of the American Mosquito Control Association, June, 2005).

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  1. VF

    I have used this method for years to avoid the after-effects of insect bites. Put a little liquid on the bite and sprinkle with Adolf’s Meat Tenderizer (unseasoned). Make a paste and rub it in. The tenderizer brakes down the protein in the toxin, and the itching and swelling don’t occur. You should do this ASAP. In the Summer, I always carry a small vial of meat tenderizer in my purse. If no liquid is available, use saliva.

  2. Elisa D

    I have been taking a multi-B vitamin complex every other day for a few weeks. We just got back from camping next to a river, and I didn’t get even one bite, even though I did not use insect repellant! Both my husband and daughter were bitten multiple times. I usually get such bad bites that I will scratch deep wounds that scar. This has made a believer out of me, but I don’t know which of the B vitamins to give credit to, I guess I’ll continue to take the multi-B complex. Maybe the studies were done with a different variety of mosquito?

  3. AC

    Go Figure. I heard also that it works and have started taking more Vitamin B’s. I live in the tropics 1/2 the year and the locals say B works too. So,maybe all the big companies that make the OFF etc,…. don’t want anything to work?

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