k. Amphotericin B (Fungizone). This agent is an antibiotic with antifungal
activity and is used both topically and systemically. Amphotericin B may exert a
"drying" effect on the skin, and in some cases, may stain the nails. This drug is
available as a cream, ointment, and parenteral injection.
Section II. ANTIHISTAMINES
Surely, you know several people who are allergic to pollen, feathers, dogs, and
other things. These people may break out in hives, sneeze, or have runny noses and
other conditions consequently. These symptoms are annoying, but some allergic
reactions can prove to be fatal, as in the case of anaphylactic shock, which can lead to
death in a few minutes. The group of drugs known as antihistamines is used primarily
in allergic reactions, as sedatives, and in the treatment of certain specified disorders.
To fully understand the action of these drugs, it is necessary to look at allergies and
how they are caused.
IMPORTANT TERMS AND DEFINITIONS PERTAINING TO ALLERGIES
a. Allergy. Allergy is defined as the abnormal or altered reaction to an antigen.
Certain individuals have an excessive or exaggerated sensitivity to a substance that
does not affect a normal individual. Allergy may also be thought of as a side effect of
immunity. In immunity, the antigen-antibody reactions take place in the circulatory
system. In allergy, however, the antigen antibody reactions take place in contact with
b. Allergic Reaction. The allergic reaction begins with the introduction of an
antigen into the body of an individual. Abnormal (incomplete univalent) antibodies are
then formed by the plasma cells and are found in great numbers around tissue cells.
When the antigen is again introduced into the body, the antigen antibody reaction
occurs in contact with the cells. This reaction damages cells, the cells swell and burst;
consequently, large amounts of a chemical called histamine, are released in the body.
Mast cells, which contain large amounts of histamine, are found around capillary walls.
These cells are particularly susceptible to damage caused by the antigen antibody