Under the heading of this subject we deal with stings by arthropods, making reference to the differences that exist between the stings of wasps and bees, commenting on the composition of the poisons and the different local and general reactions that are caused by such stings. Also discussed are the stings/bites caused by scorpions, spiders, ticks, and marine animals, with the clinical picture they provoke and the treatment that must be administered. Finally, snakebites are considered, with reference to the most frequent types of ophidia to be found in Navarra, how to differentiate between the bites of snakes and vipers, the different clinical pictures they provoke and the treatment to be applied