ABSTRACT
Bronchodilators are the mainstay of current therapy in chronic obstructive pulmonary disease (COPD), and while they provide relatively little improvement in spirometric lung function compared to asthma, theymay significantly reduce symptoms of dyspnea by reducing the increased lung volumes, and may also improve exercise tolerance [1]. Anticholinergics are the most effective class of brochodilators in the management of COPD [2,3]. Currently available anticholinergic drugs include ipratropium bromide, oxitropium bromide, and, more recently, tiotropium bromide, which work by blocking the receptors (muscarinic receptors) for the neurotransmitter acetylcholine, which is released from cholinergic nerve endings in the airways. Recently there have been important advances in this field, with the discovery of several distinct types ofmuscarinic receptor, raising the possibility thatmore selective drugs may be developed. Existing anticholinergic drugs have to be delivered several times a day so, as with h2-agonists, once-daily preparations would be of great advantage in the long-term management of patients with chronic airway diseases. Important advances have been made in both areas of drug development, leading to the first of a new generation of anticholinergics.
