Capsules are small, cylindrical, gelatin containers that hold dry powder or liquid medicinal agents (Figure 9-1). They are available in a variety of sizes, and they are a convenient way of administering drugs that have an unpleasant odor or taste. They do not require coatings or additives to improve the taste. The color and shape of the capsules as well as the manufacturer’s symbol on the capsule surface are means of identifying the product.

Timed-Release Capsules

Timed-release or sustained-release capsules provide a gradual but continuous release of a drug, because the granules in the capsule dissolve at different rates (Figure 9-2). The advantage of this delivery system is that it reduces the number of doses administered per day. Trade names that indicate that the drug is a timed-release product are Spansules, Gyrocaps, and Contin.

Medication Safety Alert

Timed-release capsules should NOT be crushed or chewed or have their contents emptied into food or liquids, because this may alter the absorption rate and could result in a drug overdose or subtherapeutic activity.

Tablets are dried powdered drugs that have been compressed into small disks. In addition to the drug, tablets also contain one or more of the following ingredients: binders, which are adhesive substances that allow the tablet to hold together; disintegrators, which are substances that encourage dissolution in body fluids; lubricants, which are required for efficient manufacturing; and fillers, which are inert ingredients that make the size of the tablet convenient. Tablets are sometimes scored or grooved (Figure 9-3, A); the indentation may then be used to divide the dose. When possible, it is best to request that the exact dose be prescribed rather than to attempt to divide even a scored tablet.

Tablets can be formed in layers (see Figure 9-3, B). This method allows otherwise incompatible medications to be administered at the same time.

An enteric-coated tablet has a special coating that resists dissolution in the acidic pH of the stomach but that is dissolved in the alkaline pH of the intestines (see Figure 9-3, C). Enteric-coated tablets are often used for administering medications that are destroyed by an acid pH.

A tablet that rapidly dissolves (usually within seconds) when placed on the tongue is known as an orally disintegrating tablet. These are differentiated from lozenges and from sublingual and buccal tablets, which take more than a minute to dissolve. Orally disintegrating tablets may be used for their rapid onset of action (e.g., for the treatment of migraine headache); for patients who have difficulty swallowing (e.g., patients with parkinsonism, Alzheimer’s disease, or after a stroke); and for those for whom administration must be ensured (e.g., patients with schizophrenia, who often attempt to avoid prescribed medication).

Unit-dose packaging or single-dose packaging provides a single dose of medication in one package that is ready for dispensing (Figure 9-4). The package is labeled with both the generic and brand names, the manufacturer, the lot number, and the date of expiration. Depending on the distribution system, the patient’s name may be added to the package by the pharmacy. Most unit-dose package labels include a bar code for administration, the electronic charting of medication administration, and inventory control (Figure 9-5).

A soufflé cup is a small paper or plastic cup that is used to transport solid medication forms such as capsules and tablets to the patient to prevent contamination by handling (Figure 9-6). A tablet that must be crushed can be placed between two soufflé cups and then crushed with a pestle. This powdered form of the tablet can then be administered in a solution, if soluble, or it may be mixed with a small amount of food (e.g., applesauce).

A medicine cup is a plastic container with scales (metric, household) for measuring liquid medications (Figure 9-7). Examine the medicine cup carefully before pouring any medication to ensure that the proper scale is being used for measurement (Table 9-1). The medicine cup should be placed on a hard surface when measuring liquid medication and then read at eye level. The medicine cup is inaccurate for measuring doses of less than 1 teaspoon, although it is reasonably accurate for larger volumes. A syringe comparable to the volume to be measured should be used for smaller volumes. For volumes of less than 1 mL, a tuberculin syringe should be used.

The medicine dropper may be used to administer eyedrops, eardrops, and, occasionally, pediatric medications (Figure 9-8). There is great variation with regard to the size of the drop formed, so it is important to use only the dropper supplied by the manufacturer for a specific liquid medication. Before drawing medication into a dropper, it is necessary to become familiar with the calibrations on the barrel. After the medication is drawn into the barrel, the dropper should not be tipped upside down, because the medication will run into the bulb, thereby causing some loss of the medication. Medications should not be drawn into the dropper and then transferred to another container for administration, because part of the medication will adhere to the second container, thus diminishing the dose delivered.

Doses of most liquid medications are prescribed in terms using the teaspoon as the unit of measure (Figure 9-9). However, there is great variation between the volumes measured by various spoons in the home. In the hospital, 1 teaspoon is converted to 5 mL (see Table 9-1), and this is read on the metric scale of the medicine cup. For home use, an oral syringe is recommended. If this is not available, a teaspoon that is used specifically for baking may be used as an accurate measuring device.

A plastic oral syringe may be used to measure liquid medications accurately (Figure 9-10). Various sizes are available to measure volumes from 0.1 to 15 mL. Note that a needle will not fit on the tip.

An infant feeding nipple with additional holes may be used for administering oral medications to infants (Figure 9-11). (See also “General Principles of Liquid-Form Oral Medication Administration—For an Adult or Child” on p. 132.)