CHAPTER  7 ORAL PHARMACOLOGY 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 dentistry. 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 patient’s 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. DRUG STANDARDS 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. DOSAGE 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. Therapeutic Dose 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 effect. Dosage Range 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 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 others. Weight 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. 7-1