Anticholinergics produce bronchodilatation by their vagolytic effects. They work by competitively inhibiting acetylcholine at the muscarinic cholinergic receptor. Acetylcholine stimulates the enzyme guanyl cyclase, which is responsible for converting guanosine triphosphate to cyclic GMP which mediates bronchoconstriction. In asthma and chronic obstructive pulmonary disease, improvements in forced expiratory volume in 1 s and hospital admission rates have been demonstrated with a combination of an anticholinergic and a b-agonist compared with using b-agonists alone. Certain patient subgroups seem to benefit, including those with chronic obstructive airways disease, those with severe airflow obstruction, or those receiving b-blockers. Inhaled ipratropium bromide is the agent of choice as its quaternary ammonium structure minimizes its systemic absorption and thus its side-effects.
The onset of action is 15 to 30 min after inhalation, with the peak effect at 30 to 60 min. Action persists for 4 to 6 h. There are almost no side-effects when the inhaled route is used, although higher doses may produce dry mouth, urinary retention, and constipation. Cautions include glaucoma, prostatic hypertrophy, and pregnancy.
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Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.