must be in a fine degree of subdivision. Label suspensions with a “Shake Well” label. USES: Suspensions are used for the administration of oral medicaments, which have low volubility in water or aqueous vehicles. Also, suspensions are used for parenteral drugs and ophthalmic solutions.
OINTMENTS
Ointments are semisolid, fatty, or oily preparations of medicinal substances of such consistency as to be easily applied to the skin and gradually liquefy or melt at body temperature. Ointments vary in color according to their ingredients. The base of an ointment is generally of a greasy character, and the medicinal substances combined with it are always intended to be in very fine particles, uniformly distributed.
Methods of Preparation
Incorporation: The medicinal substances are finely powdered, if necessary, and then they are levigated into the fatty base, either in the mortar or on the ointment tile.
Fusion: The fatty base is melted, then the finely powdered ingredients are added and mixed thoroughly. The solution is cooled so that the base, now containing the medicinal substances, returns to its natural state.
USES: Ointments have long been a preferred form for the external application of medicinal substances. In addition to the action of the medicinal substances combined with them, the fatty bases are emollient and protective in nature.
Example: Zinc Oxide Ointment
SUPPOSITORIES
They are solid bodies intended to introduce medicinal substances into the various orifices of the body. The ingredients are incorporated in a base that melts at body temperature. They are of the following types:
Methods of Preparation
Fusion method: The ingredients are added to melted theobroma oil (cocoa butter), and the mixture poured into the suppository mold. The mixture is allowed to cool, and the suppositories are removed from the mold.
Hand Method: The medicinal ingredient is combined with theobroma oil, and the mixture is triturated into a pliable mass. The mass is rolled by hand into the shape of a cylinder and divided into the required number of equal parts, which are then formed into the desired shape.
USES: Suppositories are commonly used for the local application of medicinal substances, as in the treatment of hemorrhoids. Occasionally suppositories are used in administering medicinal substances when administration by mouth is not practical.
CAPSULES
Capsules are gelatin shells containing solid or liquid medicinal substances to be taken orally. The most common type of capsule is that in which the medicine, in the form of a dry powder, is enclosed in transparent cases made of gelatin. They are in sized universally designated by numbers: 5, 4, 3, 2, 1, 0, 00, 000. The number 5 has the capacity of about 65 mg of aspirin powder and the 00 about 975 mg of the same substance. It should be noted that only sizes 3 through 00 are available through the Federal Stock System.
INCOMPATIBILITIES
An understanding of incompatibilities can save the pharmacy technician valuable time in compounding as well as ensure the therapeutic efficiency of the products. Incompatibilities are divided into three classes: therapeutic, physical, and chemical.
THERAPEUTIC
This type of incompatibility occurs when agents antagonistic to one another are prescribed together. Such circumstances seldom occur, but when they do it does not necessarily indicate a moment of forgetfulness on the part of the physician. Such agents may have been used together in order for one agent to modify the activity of
