Related Experiment Video
Updated: Jun 9, 2026

Dry Powder and Nebulized Aerosol Inhalation of Pharmaceuticals Delivered to Mice Using a Nose-only Exposure System
Published on: April 6, 2017
Abstract:
Inhaled antimuscarinic drugs have modest symptomatic efficacy in patients with chronic obstructive pulmonary disease (COPD). They also have several atropinic adverse effects, including mydriasis, visual disorders, dry mouth, constipation, micturition difficulties and tachycardia. In March 2008, the US Food and Drug Administration reported an increased frequency of stroke in COPD patients receiving tiotropium in clinical trials. A metaanalysis of 17 double-blind randomised trials in 13 645 patients with COPD showed a statistically significant increase in the risk of myocardial infarction, stroke and cardiovascular death associated with inhaled antimuscarinic drugs (ipratropium or tiotropium). A trial published after this metaanalysis, the Uplift study, including 5993 COPD patients followed for 4 years, showed no statistically significant difference in the frequency of cardiovascular death, myocardial infarction or stroke in the inhaled tiotropium group compared with the placebo group. However, these results are not sufficient to dispel the strong suspicion of an increased risk of cardiovascular adverse effects. In practice, the use of an inhaled antimuscarinic drug should be discussed on a case by case basis, weighing the only modest benefits against the worrisome risk of cardiovascular events.
Related Concept Videos
Antiasthma Drugs: Muscarinic Receptor Antagonists
Antimuscarinic agents compete with ACh for the same binding site on the muscarinic receptors. By binding to these receptors, they inhibit the downstream effects of ACh and block the parasympathetic...
Cholinergic Antagonists: Pharmacological Actions
Gastrointestinal Effects: Antimuscarinics reduce gut contractions, increase gastric emptying, and slow intestinal transit. They partly inhibit gastric acid secretion...
Cholinergic Antagonists: Therapeutic Uses
Respiratory Tract: Ipratropium, aclidinium, and tiotropium treat asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). They protect against bronchoconstriction caused by irritants like cigarette smoke, sulfur dioxide, and ozone. They also help reduce nasopharyngeal secretions in common...
Cholinergic Antagonists: Pharmacokinetics
Nondepolarizing (Competitive) Neuromuscular Blockers: Pharmacological Actions
Although all competitive neuromuscular blockers are designed...
Direct-Acting Cholinergic Agonists: Pharmacological Actions

