Page 376 - Basic _ Clinical Pharmacology ( PDFDrive )

362 SECTION IV Drugs with Important Actions on Smooth Muscle

SUMMARY Drugs Used in Asthma

Subclass, Mechanism of Pharmacokinetics,
Drug Action Effects Clinical Applications Toxicities
BETA AGONISTS
• Albuterol Selective β 2 agonist Prompt, efficacious bronchodilation Asthma, chronic obstructive Aerosol inhalation • duration several
pulmonary disease (COPD) hours • also available for nebulizer and
• drug of choice in acute parenteral use • Toxicity: Tremor,
asthmatic bronchospasm tachycardia • Overdose: arrhythmias

• Salmeterol Selective β 2 agonist Slow onset, primarily preventive Bronchodilation, prevention of Aerosol inhalation • duration 12–24 h
action; potentiates corticosteroid asthma exacerbations • Toxicity: Tremor, tachycardia • Overdose:
effects arrhythmias
• Metaproterenol, terbutaline: Similar to albuterol; terbutaline available as an oral drug
• Formoterol, vilanterol: Similar to salmeterol

• Epinephrine Nonselective α and Bronchodilation plus all other Anaphylaxis, asthma, others Aerosol, nebulizer, or parenteral
β agonist sympathomimetic effects on (see Chapter 9) • rarely used for • see Chapter 9
cardiovascular and other organ asthma (β 2 -selective agents
systems (see Chapter 9) preferred)
• Isoproterenol β 1 and β 2 agonist Bronchodilation plus powerful Asthma, but β 2 -selective agents Aerosol, nebulizer, or parenteral
cardiovascular effects preferred • see Chapter 9
CORTICOSTEROIDS, INHALED
• Fluticasone Alters gene Reduces mediators of inflammation Asthma • adjunct in COPD Aerosol • duration hours • Toxicity:
expression • powerful prophylaxis of • hay fever (nasal) Limited by aerosol application • candidal
exacerbations infection, vocal cord changes
• Beclomethasone, budesonide, flunisolide, others: Similar to fluticasone
CORTICOSTEROIDS, SYSTEMIC
• Prednisone Like fluticasone Like fluticasone Asthma • adjunct in COPD Oral • duration 12–24 h • Toxicity:
Multiple • see Chapter 39
• Methylprednisolone: Parenteral agent like prednisone

STABILIZERS OF MAST AND OTHER CELLS
• Cromolyn, Alter function of Prevention of bronchospastic Asthma (other routes used for Aerosol • duration 6–8 h • Toxicity: Cough
nedocromil delayed chloride response to allergen inhalation ocular, nasal, and • not absorbed so other toxicities are
(no longer channels • inhibit gastrointestinal allergy) minimal
available in inflammatory cell
the USA) activation
METHYLXANTHINES
• Theophylline Uncertain: Bronchodilation, cardiac stimulation, Asthma, COPD Oral • duration 8–12 h but extended-
• phosphodiesterase increased skeletal muscle strength release preparations often used • Toxicity:
inhibition (diaphragm) Multiple (see text)
• adenosine
receptor antagonist

• Roflumilast: Similar to theophylline, but with better therapeutic ratio
LEUKOTRIENE ANTAGONISTS
• Montelukast, Block leukotriene Block airway response to exercise Prophylaxis of asthma, Oral • duration hours • Toxicity: Minimal
zafirlukast D 4 receptors and antigen challenge especially in children and in
aspirin-induced asthma
• Zileuton: Inhibits lipoxygenase, reduces synthesis of leukotrienes
IgE ANTIBODY
• Omalizumab Humanized IgE Reduces frequency of asthma Severe asthma inadequately Parenteral • duration 2–4 weeks • Toxicity:
antibody reduces exacerbations controlled by above agents Injection site reactions (anaphylaxis
circulating IgE extremely rare)
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