C H A P T E R 5 4
Drugs acting on the upper respiratory tract
843
D
rugs that affect the respiratory system work to keep
the airways open and gases moving efficiently. The
classes discussed in this chapter mainly act on the upper
respiratory tract. Figure 54.1 shows structures of the
upper respiratory tract. Figure 54.2 displays the sites of
action of these drugs.
ANTITUSSIVES
Antitussives
are drugs that suppress the cough reflex (Table
54.1). Many disorders of the respiratory tract, including
the common cold, sinusitis, pharyngitis and pneumonia,
are accompanied by an uncomfortable, unproductive
Topical nasal decongestants,
nasal steroid work here
Codeine, dextromethorphan
work here
Mucus
Medullary
cough centre
Mucolytics
work here
Inhaled
steroids
work here
Guaifenesin
works here
Alveoli
Antihistamines
work here
Bronchodilators
work here
Lung surfactants
work here
FIGURE 54.2
Sites of action of drugs acting
on the upper respiratory tract.
Sphenoid sinus
Frontal sinus
Superior turbinate
Middle turbinate
Inferior turbinate
Nose
Nares
Tongue
Lingual
tonsils
Epiglottis
Vocal cord
Glottis
Larynx
(voice box)
Oesophagus
Laryngopharynx
Oropharynx
Opening to
eustachian tube
Nasopharynx
Adenoids
(pharyngeal tonsils)
FIGURE 54.1
Structures of the upper respiratory tract.
