6-9.
COMPONENTS OF A TABLET
You closely observe two tablets that are the same size. One tablet is labeled
325-mg while the other tablet is labeled 500-mg. How can this be nice? They are the
same size. Tablets contain ingredients other than the active ingredient as stated on the
drug container label. Most tablets contain at least five ingredients. Other tablets
contain additional ingredients (for example, sweeteners and coloring agents). The
following five components are often found in tablets:
a. Active ingredient. The active ingredient is the chemical substance that is to
produce a desired pharmacological effect in the patient.
b. Binder. The binder is the substance that holds the tablet together.
c. Diluent. The diluent is the "filler" that provides the desired extra volume for
the tablet. For example, imagine a tablet that is labeled 2-mg. Actually, the tablet might
weigh 175 mg. Does this mean the manufacturer made a mistake and put too much
active ingredient in the tablet? Probably not. Much of this extra weight is diluent.
d. Lubricant. A lubricant is a substance that serves two functions. First, the
lubricant prevents wear and tear on the tablet-making machine. Second, it makes it
easier for the tablet to be removed from the tablet-forming mold.
e. Disintegrant. A disintegrant helps the tablet break apart and dissolve in the
patient's gastrointestinal tract. Many disintegrants act by absorbing water and splitting
the tablet into many small pieces.
6-10. TYPES OF TABLETS
Many types of tablets exist. Tablets are frequently categorized based upon their
use.
a. Common Oral Tablets.
(1) Definition. An oral tablet is a solid medicated dosage form made by
compression or molding and intended to be swallowed whole.
(2) Use. The oral tablet is used when the patient is able to swallow and the
drug is not hindered by gastric juices.
b. Chewable Tablets.
(1)
Definition. A chewable tablet is a tablet meant to be chewed before
swallowing.
MD0809
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