Biochemical properties, pharmacokinetics and pharmacological response of tiotropium in chronic obstructive pulmonary disease patients

Background: Chronic obstructive pulmonary disease (COPD) is a progressive disease with increasing incidence and mortality. Tiotropium is an inhaled long-acting anti-cholinergic for the maintenance treatment of COPD. Objective: To review biochemical and pharmacokinetic data on tiotropium and discuss in the context of tiotropium's efficacy and safety in COPD. Methods: Review of previously done pharmacokinetic studies performed by the manufacturer of tiotropium. Data obtained through peer-reviewed publications and regulatory websites. Results/conclusions: The long duration of action with tiotropium is owing to prolonged, competitive binding to M-3 muscarinic receptors. Tiotropium is poorly absorbed following inhalation, which largely limits side effects. Metabolism of absorbed drug is minimal and excretion is largely through the kidneys. Tiotropium is efficacious and well tolerated by patients with COPD.