b. Antigen--a substance which when injected into the body stimulates
production of antibodies and therefore promotes active immunity.
c. Antibody--substances produced by the body for its protection when
pathogenic microorganisms are present in the tissues, or when an antigenic substance
has been injected into the body.
d. Toxin--a poisonous substance produced by certain pathogenic
microorganisms. Toxins stimulate the production of antibodies and thus act as
e. Toxoid--a suspension of a toxin, modified so that it no longer produces toxic
effects in the body but still acts as an antigen.
f. Vaccine--a suspension of either weakened or killed bacteria or viruses,
administered to create active immunity to an infectious disease.
g. Antitoxin--type of antibody formed in the body of an animal that has been
selectively and actively immunized. Blood serum from the animal is obtained and
purified; it is used to neutralize the toxins produced in certain diseases (e.g., tetanus).
Thus, it is used to produce passive immunity.
h. Immune Serum--blood serum from either animals or humans that have been
infected with the disease. Such serum contains antibodies against the particular
disease-producing organisms involved; passive immunity is produced.
ALLERGIC (HYPERSENSITIVE) REACTIONS
a. Serum Sickness. Following injection of a drug containing animal serum,
after a period of 5-14 days, there may be the sudden appearance of skin rash, fever,
glandular inflammation, and joint pain. Serum sickness may last from several days to
several weeks. It may require the administration of corticosteroids for its relief.
b. Drug Fever. In drug fever, a fever of up to 104F appears 7-21 days after the
use of a drug. Drug fever usually lasts about 2-3 days after discontinuation of the drug.
c. Anaphylactic Reaction. Anaphylactic reactions are unusually strong allergic
reactions to the administration of a drug. Histamine is released in the body, producing
urticaria (a vascular reaction characterized by reddish, pale, smooth, slightly elevated
skin patches attended by severe itching), bronchial spasms, laryngeal edema,
hypotension, and sometimes shock. An anaphylactic reaction may be lethal, but
preparation for treatment, early recognition, and promptness of treatment reduce the
possibility of death. The immediate treatment begins with the IM or IV administration of
1.0 ml of a 1:1000 solution of epinephrine. Epinephrine acts as a physiological
antagonist of histamine. The most dangerous anaphylactic reactions occur very soon