The risks of side effects from DTP (diphtheria and tetanus toxoids and pertussis vaccine absorbed USP) were greater than the form of the vaccine used today, the DTaP. Today, the safer DTaP vaccine has the potential of causing the same side effects, but they are less likely to occur. This vaccine can cause mild side effects, such as tenderness at the site of the injection and a low grade fever. Some children may be tired or cranky for a couple of days after receiving the vaccine. A very small number of children have had seizures, a high fever, and crying for longer than three hours straight. Rare side effects include severe allergic reactions (including facial swelling, difficulty breathing, hives, and rash), brain damage, and coma. The risks of the DTaP vaccination are almost always considered less than the consequences of coming down with one of the illnesses prevented by the vaccine.