Diphtheria is treated by giving antitoxins and antibiotics as quickly as possible. The antitoxin is given immediately, even before lab tests confirm the diagnosis, to neutralize any unbound diphtheria toxin in the person's blood. Antibiotics such as erythromycin or penicillin G are also used to eliminate the diphtheria bacteria from the body, limit toxin release, speed up recovery, and prevent the infection from spreading to others. Close contacts of the person with diphtheria should also receive antibiotics to stop the infection from spreading.