Chapter 55 Drug that act on the lower respiratory tract

What are bronchodilators?

These are drugs that relax bronchial smooth muscles, which causes dilation of the bronchi and bronchioles that are narrowed. There are three types.

What are the three classes of bronchodilators?

• beta-adrenergic agonists (sympathomimetic)

• Anticholinergics

• Xanthin derivatives

Bronchodilators, Beta-adrenergic agonists albuterol short acting

These are used in the treatment and prevention of asthma attacks. They quickly reduced airway constriction and restore normal airflow; bronchospasm related to asthma, bronchitis. Also used in hypotension and shock

Bronchodilators, Beta-adrenergic agonists long-acting salmeterol

Long acting beta 2 agonist bronchodilator, never used for acute treatment. Use for the maintenance treatment of asthma and COPD. Used. as a conjunction with an inhaled corticosteroid. Should be never given more than twice daily.

Sympathomimetics (epinephrine)

These mimic effects of he sympathetic nervous system, dilation of bronchi with increased rate and depth of respiration.

Sympathomimetics (epinephrine) actions

Beta 2 selective adrenergic agonists.

Sympathomimetics (epinephrine) Indications

Acute asthma attack, bronchospasm in acute or chronic asthma, prevention of exercise-induced asthma. Allergy anaphylaxis.

Sympathomimetics (epinephrine) contraindications

Depends on the severity of the underlying conditon

Sympathomimetics (epinephrine) Adverse effects

Sympathomimetic stimulation, CNS stimulation, Gi upset, cardiac arrhythmias, hypertension, bronchospasm, sweating, pallor and flushing.

Sympathomimetics (epinephrine) drug to drug interactions

General anesthetics

Sympathomimetics (epinephrine) therapeutic effects

Decreased dyspnea, wheezing, restlessness and anxiety. Improved respiratory patterns with return to normal rate and quality. Improved activity tolerance and decreased symptoms and increase ease of breathing.

Xanthines (theophylline) actions

Direct effects on the smooth muscles of the respiratory tract, both in the bronchi and in the blood vessels.

Xanthines (theophylline) indications

Symptomatic relief or prevention of bronchial asthma and for reversal of bronchospasm associated with COPD

Xanthines (theophylline) Pharmacokinetics

There is a narrow therapeutic margin.

Xanthines (theophylline) contraindications

GI problems, coronary disease, respiratory dysfunction, renal/hepatic disease, alcoholism or hyperthyroidism.

Xanthines (theophylline) adverse effects

related to theophylline levels in the blood, GI upset, nausea, irritability, and tachycardia to seizure, brain damage and death.

Xanthines (theophylline) Drug to Drug interaction

Many drug interact with these and substance in cigarettes also interact with these.

Anticholinergic (ipratropium)

Patient’s who can not tolerate the sympathetic effete of sympathomimetic might respond better to these

Anticholinergic (ipratropium) Actions

Anticholinergic that blocks vaguely mediated reflexes by antagonizing the action of acetylcholine.

Anticholinergic (ipratropium) Indications

Maintenance and treatment of bronchospasm associated with COPD

Anticholinergic (ipratropium) Pharmacokinetics

Onset of the action is 15 minutes when inhaled and it peaks in 1-2 hrs.

Anticholinergic (ipratropium) Caution

Any condition that would be aggravated by the anticholinergic effects of the drug.

Anticholinergic (ipratropium) adverse effects

Related to the anticholinergic effects of the drug. Dizziness, headache, fatigue, nervousness, dry mouth, sore throat, palpitations and urinary retention

Anticholinergic (ipratropium) drug to drug interactions

Other anticholinergics

Inhaled steroids (fluticasone) action

Decreases the inflammatory response in the airway.

Inhaled steroids (fluticasone) Indications

Prevention and treatment of asthma, very effective treatment for brochospas,. Used to treat chronic steroid-dependent bronchial asthma.

Inhaled steroids (fluticasone) contraindications

This is not used for emergency during an acute attack or status asthmaticus. Can not be used with pregnancy lactations, not to be used as sole medication for asthma, hypersensitivity to glucocorticoids and not used for patients with systemic fungal infection.

Inhaled steroids (fluticasone) Adverse effects

Sore throat, hoarseness, coughing, dry mouth, pharyngeal/laryngeal fungal infections.

What should throughly be assessed before any theraphy?

Skin color, baseline VS, sputum production, allergies, history of respiratory problems, other medication and smoking history.