Respiratory tract bronchodilation

Leuko trienes are bronchoconstrictive substances released by the body during the inflammatory process. When leukotriene production is inhibited, bronchodilation is facilitated. Zileuton acts by decreasing tire formation of leukotrienes. Although the result is tire same, montelukast and zafirlukast work in a manner slightly differently from that of zileuton. Montelukast and zafirlukast are considered leukotriene receptor antagonists because they inhibit leukotriene receptor sites in the respiratory tract, preventing airway edema and facilitating bronchodilation. 

The importance of tobacco includes both those constituents in smoke that may interact with nicotine directly, as well as those that indirectly influence a smoker s perception and behaviors. For example, some tobacco smoke constituents may alter the site of absorption of nicotine, such as bronchodilators (e.g., cocoa, licorice), which allow deeper inhalation and subsequent deposition of constituents in more highly permeable areas of the respiratory tract. Likewise, product changes to alter or control particle size, or to provide particulate carriers for vapor-phase smoke constituents, also could facilitate changes at the site of absorption (Ingebrethsen 1993). This would also include the use of acids or bases to alter the form of nicotine and basicity of smoke. Again, a wide range of relevant findings is indicated by internal documents (Ferris Wayne et al. 2006 Keithly et al. 2005 Pankow 2001). 

Isoetharine is a direct-acting sympathomimetic with relatively low selectivity with j32-adrenoreceptors. However, it quickly calms bronchospasms better than more selective bronchodilators. It is used in treating chronic obstructive illnesses of outer respiratory tract. Synonyms of this drug are asthmalitan and bronkosol. 

B. Status asthmaticus is a dangerous exacerbation of asthma symptoms. It requires immediate and aggressive treatment with oxygen, inhaled bronchodilators, and systemic corticosteroids. Hospitalization of the patient is often indicated. By definition, status asthmaticus is not a condition in which symptoms are well controlled. Neither cromolyn sodium nor a leukotriene modulator is indicated for the treatment of status asthmaticus, as their onset of action is too slow. Status asthmaticus often does not resolve without aggressive intervention. Indeed, the patient s condition can deteriorate rapidly to death. Upper respiratory tract infection or excessive exposure to an allergen often precedes status asthmaticus, as does increased use of inhaled bronchodilators. 

Mechanism of Action A second-generation piperazine that competes with histamine for Hj-receptor sites on effector cells in the GI tract, blood vessels, and respiratory tract. Therapeutic Effect Prevents allergic response, produces mild bronchodilation, blocks histamine-induced bronchitis. 

Bronchial smooth muscle contains B2 receptors that cause relaxation. Activation of these receptors results in bronchodilation (see Chapter 20 Drugs Used in Asthma and Table 9-3). The blood vessels of the upper respiratory tract mucosa contain receptors the decongestant action of adrenoceptor stimulants is clinically useful (see Clinical Pharmacology). 

Q1 The most commonly used reliever in asthma therapy is a short-acting bronchodilator, such as the beta-2-agonists (/ -agonists) salbutamol or terbutaline. These are safe and effective agents for mild to moderate symptoms and are taken directly into the respiratory tract via an inhaler device. 

Spacer devices are useful to deliver drugs into the respiratory tract of young children with asthma. They reduce the deposition of bronchodilator drugs in the pharynx and require little coordination by the patient to deliver the required dose. 

INHALATIONAL- HALOTHANE TERBUTALINE, THEOPHYLLINE Cases of arrhythmias when these bronchodilators are co-administered with halothane Possibly due to sensitization of the myocardium to circulating catecholamines by the volatile anaesthetics to varying degrees Risk of cardiac events is higher with halothane. Desflurane is irritant to the upper respiratory tract, and t secretions can occur and are best avoided in patients with bronchial asthma. Sevoflurane is non-irritant and unlikely to cause serious adverse effects... 

In the respiratory tract, ipratropium s is a useful bronchodilator in chronic obstructive pulmonary disease and acute asthma. 

Enflurane is usually not irritant to the respiratory tract, although bronchospasm has been reported (8). However, it is generally considered to be a bronchodilator. It causes respiratory depression at concentrations over 2%. 

Salmeterol 42 micrograms bd has been compared with inhaled ipratropium bromide 36 micrograms/day and inhaled placebo in a randomized, double-blind study for 12 weeks in 405 patients with chronic obstructive pulmonary disease (6). Both salmeterol and ipratropium bromide significantly increased the peak expiratory flow rate compared with placebo. Non-specific ear, nose, and throat symptoms (for example sore throat and upper respiratory tract infections) were more common with salmeterol and ipratropium than placebo. There were no significant differences between the groups in the total number of ventricular and supraventricular extra beats. There was no tolerance to the bronchodilating effects of salmeterol. 

The magnitude and duration of drug concentrations above MIC in respiratory secretions after aerosol administration indicate that mhalation therapy may be a suitable option for some bacterial infections of the lower respiratory tract. Pretreatment with a short-acting, aerosolized bronchodilator, such as albuterol sulfate, may improve the pulmonary distribution of aerosolized antimicrobial drugs. 

Respiratory tract. Eicosanoids produced by certain white blood cells, the leukotrienes (see Figure 18.4), promote the constriction of the bronchi associated with asthma. Other prostaglandins promote bronchodilation. 

Drug droplets, vapor, or gas are administered dirou i die mucous membranes of the respiratory tract widi die use of a face mask, a nebulizer, or a positive-pressure breadiing machine Eixamples of dm administered dirough inhalation include bronchodilators, mucoljd-ics, and some anti-inflammatory dm. These dni produce, primarily, a local effect in die lun. ... 

Systemic (Listed in Table 10.2)) Decrease inflammation and edema in respiratory tract. Enhance activity of sympathomimetics in hypoxic and acidotic states. Asthma which can not be controlled by sympathomimetics (bronchodilators) alone. Sodium/water retention and subsequent cardiovascular problems, weakness, osteoporosis, peptic ulcers. 

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