b. Other Antitussives. Other antitussives include the following:
(1) Dextromethorphan hydrobromide. This antitussive is a morphine
derivative, but it has few of the observable properties of a narcotic. No cases of
addiction or severe central nervous system depression have been reported with it.
(2) Benzonatate (Tessalon). This drug has an effect on the mucous
membranes of the respiratory system similar to that of a local anesthetic. In addition,
like the other antitussives discussed, it has an effect on the nerve connections in the
medulla concerned with the cough reflex. It does not appear to be as effective clinically
Expectorants are drugs that increase the volume of secretions from the mucous
membranes of the respiratory tract below the epiglottis. They also help liquefy the
mucous secretions, which are subsequently spat out by the client. Expectorants are
useful in treating coughs. Since some of the difficulty of asthma arises from obstruction
of breathing by mucus, expectorants are sometimes useful in treating asthma.
a. Potassium Iodide. Potassium iodide is one of the most effective
expectorants. Mild side effects, including weeping of the eyes and nose, sometimes
occur, but serious side effects are rare. Potassium iodide is also used to treat iodine
b. Ipecac Syrup. This preparation may be used as an expectorant, but the
dose is lower than when it is used as an emetic. It is useful when the client has
unpleasant reactions to potassium iodide.
c. Ammonium Chloride. As is part of the effect of potassium iodide, the
expectorant effect of ammonium chloride is due to its irritation of the stomach lining.
Large doses may cause nausea.
d. Guaiafenesin. In large doses, this is an effective expectorant. It is an
ingredient in many cough syrups.
e. Terpin Hydrate. This drug can be used as an expectorant but terpin hydrate
elixir, NF, does not contain enough terpin hydrate to make the elixir a useful