Glycopyrronium for inhalation. COPD: another antimuscarinic with cardiac adverse effects that require monitoring.

The most effective way of slowing chronic obstructive pulmonary disease (COPD) progression is to eliminate exposure to the inhaled triggering factor, which is usually tobacco smoke. At best, inhaled bronchodilators have only a limited impact on the symptoms of COPD. In the absence of a better alternative, salbutamol, a beta-2 agonist, or ipratropium, an antimuscarinic, are tried first, despite their adverse effects. "Long-acting" beta-2 agonists are an option for patients with permanent symptoms, especially dyspnoea that disrupts sleep. Glycopyrronium, a long-acting antimuscarinic, is authorised in the European Union for maintenance treatment of adults with COPD. Clinical evaluation does not include any trials versus salbutamol. It is based on three trials, in a total of 2051 patients that compared glycopyrronium versus placebo and sometimes versus tiotropium, another long-acting inhaled antimuscarinic. Mortality rates were similar in the different arms of these trials. There was no difference in efficacy between glycopyrronium and tiotropium. In two of these trials, which lasted at least 26 weeks, "serious" cardiac adverse events were more frequent with glycopyrronium than with placebo or tiotropium. However, the number of events was too small to determine the precise cardiac harms associated with glycopyrronium. The European Medicines Agency has therefore asked for a specific registry to be created. The adverse effect profile of glycopyrronium appears similar to that of inhaled antimuscarinics, including atropinic disorders and upper respiratory infections. The inhaler is simple to use and does not require hand-breath coordination. In practice, glycopyrronium does not provide a therapeutic advantage in the treatment of patients with COPD. When an inhaled long-acting drug is contemplated, it is best to choose a beta-2 agonist (formoterol or salmeterol), used either continuously or on demand.