Following a tarantula bite, tetanus prophylaxis is required if the patient has not received a DTaP vaccine in the previous 5 years. Therefore, this patient must receive the DTaP vaccine as soon as possible. Antihistamines and corticosteroids can be used for symptom management but are of less importance than tetanus prophylaxis. The tetanus immune globulin should be given to individuals who have not received the full course of tetanus vaccines, as this patient has.