Centipedes might appear alarming with their unfeasible number of legs, speed and ability to nip, but they are normally useful around the garden. They are little carnivores consuming genuine pests such as slugs and caterpillars. In the home it is another story. The centipedes themselves are harmless if you don't handle them, but they may be the sign of another problem.
Centipedes need food and moisture to survive. Their coming inside regularly may indicate the presence of dampness or other bugs. A single centipede probably just wandered in by accident, but if you often see centipedes in your house, try to determine the cause. Centipedes in the bathroom or basement are probably due to a consistently damp atmosphere, which could lead to mould or rot if ignored. Centipedes in the kitchen could also be because of humidity, probably from cooking, but could indicate there are numerous pests such as beetles. Beacuse centipedes eat these insects, a plentiful food supply could attract them indoors.
Removing the centipede or centipedes is the first step. Quickly place a glass or plastic container over the centipede, slide a piece of thin cardboard underneath and carry outside to release it where it can do some good in your garden. You should also remove any sources of moisture such as damp towels lying on the floor or over-watered pot plants.
To dissuade centipedes from returning, it is necessary to fix leaking pipes and regularly mop condensation from windows and under the refrigerator. Keeping kitchen and eating areas completely free of crumbs and covering bowls of food and pet food deters centipede prey such as beetles, roaches and ants. If you have a serious problem with one of these creatures, you may need to take further action such as laying out poisoned bait. It is normally difficult to block the entrances for the centipedes or their prey because bugs are so small, but sealing up any gaps you can find may help.
The small centipedes found in temperate regions normally do little more than nip when people pick them up and are unable to bite through human skin. In the event of a bite from a large centipede, Medline Plus recommends washing the bite with soap and water, then applying ice for ten minutes at a time to reduce pain and swelling. Centipede bites occasionally trigger allergic reactions, which need medical attention. Kill the centipede if possible for identification purposes and call your doctor, the National Poison Control Center, or emergency services. Do not handle any centipedes with your bare hands, or allow children or pets touch them as there are some species of centipedes that are toxic.