LEARNING OBJECTIVE: Recall the composition and physical characteristics of commonly used pharmaceutical preparations.
The following sections will acquaint you with the composition and physical characteristics of some common pharmaceutical preparations.
Elixirs are aromatic, sweetened hydroalcoholic solutions containing medicinal substances. The color of elixirs varies according to the nature of the ingredients; some are artificially colored.
Suspensions are coarse dispersions comprised of finely divided insoluble material suspended in a liquid medium. To keep the insoluble material suspended, a third agent, called a suspending agent, is required. The process of mixing or combining the ingredients to form a suspension is called reconstitution.
Ointments are semisolid, fatty, or oily preparations of medicinal substances. These preparations are of such a 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 greasy in texture, and the medicinal substances combined with it are always intended to be very fine particles, uniformly distributed.
Suppositories are solid bodies intended to introduce medicinal substances into the various orifices of the body (rectum, vagina, and urethra). The ingredients are incorporated in a base that melts at body temperature.
Capsules are gelatin shells containing solid or liquid medicinal substances to be taken orally. A common type of capsule contains medicine in the form of a dry powder that is enclosed in transparent cases made of gelatin. Capsules are sized by universally designated numbers: 5, 4, 3, 2, 1, 0, 00, 000. The number 5 has the capacity of about 65 mg of powder (such as aspirin) and the number 00 capsule contains about 975 mg of the same substance. Only sizes 3 through 00 are available through the Federal Stock System.