Download - Chapter 9
Chapter 9
Respiratory Drugs
Terms to Define
• Asthma• Bronchospasm• Status Asthmaticus• Metered dose inhaler
(MDI)• Spacer
• Nebulizer• Bronchodilator
Asthma
• Inflammatory disease in which inflammation causes the airways to tighten
• Reversible condition• Intermittent attacks are precipitated by
specific triggering events• Causes a decrease in the amount of
• oxygen and carbon dioxide exchanged
Asthma
• An asthmatic lung compared to a normal lung– More sensitive– Responds to lower doses of allergens
• Studies strongly support genetic predisposition to developing asthma
Characteristics of Asthma
1. Reversible small airway obstruction2. Progressive airway inflammation3. Increased airway responsiveness to variety of
stimuli4. = wheezing, dyspnea, acute & chronic cough
Asthma Attack: First Response
• Triggered by an antigen-antibody reaction• Causes degranulation of mast cells which
release histamine• Result: bronchospasm and increased mucus
production that plugs the small airways
Asthma Attack: Second Response
• Bronchoconstriction with delayed, sustained reactions
• Causes self-sustaining inflammation
Asthmatic Response
Devices Used in Asthma Therapy
• Metered dose inhaler (MDI)– Contains medication and compressed air– Delivers specific amount of medication with each puff
• Spacer– Used with MDIs to get medication into lungs instead of
depositing on back of throat
Nebulizers
• Uses stream of air that flows through liquid medication to make a fine mist for inhalation
• Very effective• Must be cleaned and taken
care of to reduce risk of contamination
• Used for young children
Short-Acting Inhaled Bronchodilators
• albuterol– Relaxes bronchial smooth muscle with little effect
on heart rate, duration of 3 to 6 hours
ProAir/Albuterol (Bronchodilator)
• Works by widening the airways in the lungs• Indicated usage:– Tx or prevent breathing problems in patients with
Asthma– Prevent breathing problems with exercise
Proventil/Albuterol (Bronchodilator)
• bronchodilator that relaxes muscles in the airways and increases air flow to the lungs– Exercise induced bronchospasm– Prevent bronchospasm in people with reversible
obstructive airway disease
Ventolin/Albuterol (Bronchodilator)
• a bronchodilator that relaxes muscles in the airways and increases air flow to the lungs
• Indicated usage– Prevent bronchospasm for people with reversible
obstructive airway disease– Prevent exercise induced bronchospasm
Dispensing Issues of albuterol
• Proventil HFA and ProAir HFA cannot be interchanged
• If Rx for an albuterol inhaler, any of the 3 brands can be used
Asthma Agents:Leukotriene Inhibitors
• Leukotrienes– Increase edema, mucus, and vascular permeability– Substances can pass through blood vessels– 100 to 1,000 times more potent than histamine
• Block synthesis of, or the body’s inflammatory responses to, leukotrienes
Montelukast/Singulair (Leukotriene Inhibitor)
• Indicated for prophylaxis and chronic treatment of asthma
• Do not use to treat acute attacks• Approved for use in adults and
children 12 months and older• Once-daily dosage• Also used to treat seasonal
allergies
Asthma Agents:Corticosteroids
• Anti-inflammatory agents that suppress the immune response
• Used for more difficult cases of asthma• Usually prescribed on alternate-day basis or as
tapering doses when short-term therapy is indicated
• Many patients with asthma still not using
Primary Side Effects of Corticosteroids
• Oral candidiasis• Irritation and burning of nasal mucosa• Hoarseness• Dry mouth
Side Effects of Long-Time Use of Oral Corticosteroids
• Growth of facial hair in females• Breast development in males• “Buffalo hump,” “moon face” • Edema• Weight gain• Easy bruising
Corticosteroids
• Always use lowest effective dose• Add salmeterol to inhaled corticosteroids if
needed to decrease the dose of corticosteroid needed for control
Dispensing Issues of Corticosteroids
• Patient should rinse mouth with water after using inhalers to prevent oral candidiasis
• Patient should be taught how to correctly use these medications
fluticasone (Flonase, Flovent) Corticosteroid
• Flonase (Flovent) is same drug in nasal spray Flonase• Flovent comes in 3 strengths– Lowest for mild asthma– Highest to wean patients off oral corticosteroids
• 1 to 2 weeks to reach maximum benefit
fluticasone-salmeterol (Advair Diskus)
• Combines corticosteroid (anti-inflammatory) and a beta-2 agonist
• Indicated for maintenance therapy in patients 12 years and older
• Available in powder for inhalation• Should not be used with a spacer
Nasal Corticosteroids
• Most effective monotherapy for allergic rhinitis
• Must be used daily• Can cause nasal irritation and bleeding; direct
spray away from septum• Local infections of Candida albicans may occur
in nose with long term use
mometasone furoate (Nasonex) (nasal corticosteroids)
• Depresses release of endogenous chemical mediators of inflammation
• Reverses dilation and permeability of vessels in area
• Children over 12 can use to prevent symptoms of allergic rhinitis
Methylprednisolone/Medrol
• Steroid- prevents the release of substances in the body that cause inflammation
• Tx- allergic disorders
Promethazine/Phenergan (antihistamine)
• Blocks effects of histamine (which triggers inflammatory response)
• Treat allergy symptoms
Fexofenadine/Allegra (Antihistamine)
• Blocks the effect of histamine in the body• Tx allergy symptoms