Entomology (Study of Bugs)/bug bites


I live in San Francisco. In the past 6 weeks Iíve been bitten several time (on the ankle and back of arms) by something at night in bed. I have never seen any sort of critters in or around my bed, so I have no photo to share. But comparing the site of the bite marks to online images, it would appear to be a centipede. I suspect that a recent re-roofing of my building has dislodged a centipede hang-out, but no real proof.
My question is ócan you share any info about the toxins that centipedes deposit during a bite? do they have lasting effects? neuro-toxic? I am keeping watch on the current bite areas for any tissue damage, but itís primarily pain and swelling.
Also, any suggestions about how to protect myself from them? I understand that cedar oil is a good repellant. Any help you can provide is appreciated.

Hi Christine,

I am sorry to hear about your bites. Without a photo, I cannot verify they were caused by a centipede. More likely they are flea, mosquito, spider, or bed bug bites. However, it is possible a centipede got into your bed and you rolled over on it. They don't feed on humans, but can bite in self-defense. The fact that you have been bitten several times over the past few weeks makes me think the bites were caused by an insect that feeds on humans (flea, mosquito, bed bug...)

I first recommend that you wash the bites with soap and water to avoid infection. Ice can help with the pain and swelling. With any type of bite, you should keep an eye on the area, keep it clean, and avoid scratching. If you have an allergic reaction to the bite, it can be serious so contact a doctor if you develop a fever or any strange symptoms. You can also call Poison Control at 1-800-222-1222.

To keep centipedes from coming inside, you should check that the windows are all sealed properly. If you see any centipedes in your home, get rid of them. I also recommend checking under and around your mattress for any insects. Look closely at the mattress seams for bugs that are hiding in the crevices. If you find anything that you want identified, send me a photo and I will respond quickly.


Entomology (Study of Bugs)

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Jessica Mellinger


I can answer questions about invertebrates native to California, including insects commonly found in homes. If you have an identification request, please attach a photo to your question.


I was involved in collection and identification of invertebrates for the United States Geological Survey, Biological Resources Division for six years. Also, I provided these same services intermittently for the UC Davis John Muir Institute of the Environment for many years. I have been a member of AllExperts.com since 2009.

Department of the Interior: United States Geological Survey, Davis Field Station; University of California, Davis Aggie Alumni Association; UC Davis Center for Neuroscience; U.S. Department of Veteran's Affairs

I have two B.A.'s from the University of California, Davis and two Associate's degrees from Sacramento City College.

Awards and Honors
Special Thanks for Achieving Results award from the Department of the Interior

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