Asthma anticholinergic agents

At this writing anticholinergic agents are not widely used for the symptomatic treatment of asthma, although compounds such as atropine [51 -55-8] C17H23NO3, (18) have been used for centuries (111). Inhalation of the smoke produced by burning herbal mixtures, such as Datura Stramonium provided bronchodilation and rehef from some of the symptoms of asthma. The major active component in these preparations was atropine or other closely related alkaloids (qv). 

Gross N Anticholinergic agents in asthma and COPD. Eur J Pharmacol 2006 8 533. 

The mode of action of theophylline is different from that of Beta2-adrenergic agonists and anticholinergic agents, so it is still used in the treatment of selected patients with asthma or chronic obstructive pulmonary disease. 

As with CB, anticholinergic agents are also rational bronchodilators for use in asthma. Their use would be expected to contribute additional bronchodilation to that provided by methylxanthines and sympathomimetic amines since the mechanism of action is directed at the effects of the non-specific stimuli. The concomitant use of all three types could also permit a more precise assessment of the non-reversible component of the patient s airways obstruction. Since many antihistamines have anticholinergic activity, it is possible that patients who take such therapy for other reasons may already have some benefit of this kind of bronchodilation. 

Two newer potent selective H -antagonists, terfenadine (23) (132) and astemizole (24) (133), have been developed which have neither the sedative nor the anticholinergic Habilities of the earlier agents. Both of these compounds have proven efficacious in the treatment of hay fever and produce very few side effects, prompting a re-evaluation of the role of antihistamines in asthma treatment. 

Anticholinergics, like atropine and its derivative ipratropium bromide block cholinergic pathways that cause airway constriction. They may provide added bronchodi-lator effect in patients who are receiving beta -adrenergic agents for asthma. 

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