1-17. EXPECTORANT AGENTS
a. Background. Expectorants are agents, which facilitate the removal of
secretions of the bronchopulmonary mucous membrane. Most of the expectorants
discussed below act reflexively by irritating the gastric mucosa. This, in turn, stimulates
secretions in the respiratory tract. Expectorants are used to remove bronchial
secretions which are purulent (containing pus), viscid (thick), or excessive. The
loosened material is then moved toward the pharynx through ciliary motion and
b. Expectorant Agents.
(1) Guaifenesin (Robitussin, Baytussin). Guaifenesin is the most
commonly used expectorant today. This nonlegend drug has the side effect of
gastrointestinal (G.I.) upset. Guaifenesin may be found alone as a syrup (100
milligrams per 5 milliliters), tablet 600 mg (Humibid L.A.), or in many combination
products such as Robitussin-DM.
(2) Saturated Solution of Potassium Iodide. Saturated Solution of
Potassium Iodide (SSKI) is an expectorant administered as 300 milligrams (10 drops) in
a glass of water or fruit juice every three or four times daily. SSKI has a very
unpleasant taste. Overdoses of this product may lead to a condition known as iodism
that produces an acne-type rash, fever, and rhinitis or runny nose. Patient compliance
with this product may be low because of its unpleasant taste. Consequently, when the
medication is dispensed you should tell the patient to place the required amount of SSKI
in fruit juice in order to mask its taste. This drug is available in a saturated solution of 1
gram per milliliter in 30 milliliter containers.
(3) Elixir of Terpin Hydrate. Elixir of Terpin Hydrate (ETH) is an
expectorant, which works directly on the bronchial secretory cells in the lower
respiratory tract to facilitate the removal of bronchial secretions. It is usually given in
doses, which range from 85 to 170 milligrams (1 or 2 teaspoonsful) 3 or 4 times daily.
The side effects of this drug are related to its alcohol content (42 percent or 84 proof). If
enough ETH is consumed it will produce significant CNS depression. Even with the
high alcohol content, ETH is an Over the Counter (OTC) product. It is available as a
syrup (85 milligrams per 5 milliliters) in 120 milliliter containers.
NOTE: Terpin Hydrate is no longer approved for use as an expectorant; it is used
mainly as a vehicle for cough mixtures.
1-18. ANTITUSSIVE-EXPECTORANT COMBINATION PRODUCTS
The antitussive-expectorant combinations are used for a hyperactive
nonproductive cough. The side effects of these drugs, or course, will be dependent on
the antitussive-expectorant combination used. Some typical combination products used