Pharmacology is a basic medical science that deals
with the study of drugs. Drugs are chemical
compounds used in the prevention, diagnosis, and
treatment of diseases and other abnormal conditions.
This chapter covers some of the drugs used in
As a Dental Technician, you will be required to
assist in procuring, labeling, and storing drugs. You
must also be aware of what drugs the dental officer
prescribes and uses during dental procedures. Certain
drugs and medicines used in dentistry have side effects
on patients, which could turn into a possible medical
emergency. Misused or mislabeled drugs can also
present a real hazard to your patients safety. You must
have full knowledge of what drugs and medicines are
being used in your clinic, hospital, or department.
Only authorized personnel should prescribe, dispense,
and administer drugs and medications. The Manual of
the Medical Department, chapter 21, gives guidance
on pharmacy operation and drug control.
Many textbooks are available that describe
commercially available drugs used in dentistry and
medicine. They provide standards for drugs of
therapeutic usefulness and pharmaceutical necessity,
and also list composition, action and use,
administration and dosage, precautions and side
effects, dosage forms available, and common (generic)
name of the drugs. Your command library is required
to have these textbooks available for use.
MEDICATION AND ADMINISTRATION
The quantity of a drug to be prescribed at one time
or the total quantity administered and method of
administration of drugs are dependent on several
factors. This section will cover some of the methods of
administering and some of the factors affecting dosage
calculations that a dental officer will use.
The amount of medication to be administrated is
referred to as dose. Doses are listed as an average
therapeutic dose and are known as "usual adult doses."
The following terms are used in connection with doses.
The therapeutic dose is also referred to as the
normal adult dose, the usual dose, or average dose. It is
the amount needed to produce the desired therapeutic
Dosage range is a term that applies to the range
between the MINIMUM amount of drug and the
MAXIMUM amount of drug required to produce the
desired effect. Many drugs, such as antibiotics, require
large initial doses that are later tapered to smaller
amounts. A TOXIC dose is the amount of drug that
will produce symptoms of poisoning; while a
MINIMUM LETHAL dose is the least amount of
drug that can produce death.
FACTORS AFFECTING DOSAGE
With the administration of medicines used in
dentistry, the dental officer must consider many
factors with each patient that affects the dose, method
of administration, and frequency of the dose.
Although a dental officer prescribes or administers the
amount to be given, you need to know how and why
these quantities are determined. Two primary factors
determine or influence the dose: age and weight.
Age is the most common factor that influences the
amount of a drug to be given. Infants, children, and
elderly patients are more susceptible to drug action and
as a general rule, should receive smaller doses than
In the calculation of dosages, weight has a more
direct bearing on the dose than any other factor,
especially in the calculation of pediatric doses.