Functional
Modifiers
They
alter the normal physiologic function or processes in the human
body. They act through interaction with drug molecules and cellular
components such as receptor that alter the functions of the latter.
Examples are analgesics that relieve pain sensation and B-blockers.
Replenishers
They
act to supplement the existing endogenous substances that are
deficient or lacking in concentration. Examples of these are Insulin
hormone, vitamin B-complex combination and electrolytes.
Diagnostic
Agents
The
are mainly used to determine the presence or absence of a condition
or disease. Examples are BaSO4, Endrophonium test (TensilonTM).
Chemotherapeutic
Agents
Used
to kill or inhibit the growth of cells (cancer cells) that are
considered foreign to the body. Examples of them are anti-infective
and anti-neoplastic agents.