Centipedes do contain a venom but the venom is usually not poisonous to the humans.
But someone may have an allergic reaction if they happen to be allergic to the venom the centipede puts out when it bites you.
Smaller centipedes usually cannot bite a human but the larger centipedes can bite humans but most times when a human gets bitten by a centipede even the large centipede they'll just have some pain for around 24 to 48 hours.