Olodaterol is a beta2-adrenoceptor agonist discovered by Boehringer Ingelheim and approved for the treatment of Chronic Obstructive Pulmonary Disease. The compound exerts its pharmacological effects by binding and activation of beta2-adrenoceptors after inhalation. Activation of these receptors in the airways results in a stimulation of intracellular adenyl cyclase, an enzyme that mediates the synthesis of cyclic-3’, 5’ adenosine monophosphate (cAMP). Elevated levels of cAMP induce bronchodilation by relaxation of airway smooth muscle cells. Olodaterol effect lasts for 24 hours.

Tiotropium is a long–acting, antimuscarinic agent, which is often referred to as an anticholinergic. It has similar affinity to the subtypes of muscarinic receptors, M1 to M5. In the airways, it exhibits pharmacological effects through inhibition of M3–receptors at the smooth muscle leading to bronchodilation. The competitive and reversible nature of antagonism was shown with human and animal origin receptors and isolated organ preparations. In preclinical in vitro as well as in vivo studies prevention of methacholine–induced bronchoconstriction effects were dose–dependent and lasted longer than 24 hours. The bronchodilation following inhalation of tiotropium is predominantly a site–specific effect. Tiotropium is a muscarinic receptor antagonist, often referred to as an antimuscarinic or anticholinergic agent. Although it does not display selectivity for specific muscarinic receptors, on topical application it acts mainly on M3 muscarinic receptors located in the airways to produce smooth muscle relaxation, thus producing a bronchodilatory effect. Tiotropium is used in the management of chronic obstructive pulmonary disease (COPD).Tiotropium bromide capsules for inhalation are co-promoted by Boehringer-Ingelheim and Pfizer under the trade name Spiriva. It is also manufactured and marketed by Cipla under trade name Tiova.