by the military are Robitussin-DM, Robitussin A-C Syrup, and Novahistine
a. Background. Mucolytics are respiratory drugs that dissolve mucous in the
respiratory tract. They are used by inhalation in an attempt to reduce the viscosity
(thickness) of respiratory tract fluid. The loosened material can then be moved toward
the pharynx more easily by ciliary motion and coughing. Like the expectorants, the
mucolytics are used in the treatment of respiratory disorders in which the secretions are
purulent (contain pus), viscid, or excessive. Consequently, the mucolytics represent an
alternative to the oral use of expectorants.
b. Mucolytic Agents.
(1) Acetylcysteine (Mucomyst). This is a mucolytic given by inhalation or
nebulization. Nebulization is treatment by spray. Two to twenty milliliters of a 10
percent drug solution or 1 to 10 milliliters of a 20 percent Mucomyst solution is
nebulized into a face mask or mouth piece every two to six hours daily. Acetylcysteine
has an unpleasant (like rotten eggs) smell. Side effects associated with this agent
include nausea and vomiting and broncho-spasms with higher concentrations (with the
20 percent solution). This medication is only dispensed for inpatient use--usually to the
respiratory therapy clinic or to the nursing station. The sterile solution should be
covered, refrigerated, and used within 96 hours after the vial is opened. It is available in
10 percent and 20 percent solutions in containers of 4, 10, or 30 milliliters.
(2) Sodium Chloride Solution U.S.P. (0.9 percent sodium chloride solution).
This agent is used alone or in combination with other mucolytic agents. Sodium
chloride solution increases the respiratory fluid volume by osmosis, which tends to
decrease the viscosity of the respiratory fluid. It is also administered by inhalation in a
nebulized form as a dense mist in a tent or delivered through a face mask or mouth
piece. The main side effect seen with sodium chloride solution occurs after prolonged
inhalation. This will cause localized irritation of the bronchial mucosa. Sodium chloride
solution for this purpose is for inpatient use by respiratory therapy personnel or by
nursing personnel. Concentrated Sodium Chloride (23.4%) is used by respiratory
therapy to induce sputum production (sputum induction procedure).
1-20. BRONCHODILATOR AGENTS
a. Background. The bronchodilators are agents that cause expansion of the air
passages of the lungs. This allows the patient to breathe more easily and are of value
in overcoming acute bronchospasms. They are employed as adjuncts in prophylactic
and symptomatic treatment of the individual complications of obstructive pulmonary
diseases such as asthma, bronchitis, and emphysema. Most of these agents have
been discussed in other lessons of the pharmacology series.