title: Anticholinergics: theoretical and clinical overview.
abstract: BACKGROUND
  Anticholinergics are a class of medicines that block the neurotransmitter, acetylcholine, in the brain and peripheral tissues. Medicines with anticholinergic activity are widely prescribed for and used by older people for various medical conditions. One-third to one-half of the medicines commonly prescribed for older people have anticholinergic activity. Several studies have reported anticholinergic burden to be a predictor of cognitive and functional impairments in older people.
  
  
  METHODS
  This article exemplifies the theoretical and clinical aspects of medicines with anticholinergic activity, including pharmacology (definition of medicines that possess anticholinergic activity, antimuscarinic receptors, therapeutic and adverse effects), epidemiology, measures and effects of cumulative anticholinergic burden in older adults, and clinical recommendations. In addition, the gaps in the literature have been identified for future research.
  
  
  CONCLUSIONS
  Many medicines that are commonly prescribed to older people have a degree of anticholinergic activity that can contribute to anticholinergic burden. Anticholinergic burden, measured in several ways that consider number, dose and/or degree of anticholinergic activity of medicines, has shown to be a predictor of adverse health and functional outcomes. The anticholinergic burden on older people should be minimised by avoiding, reducing dose and deprescribing medicines with anticholinergic activity where clinically possible.
authors.affiliation: a School of Pharmacy , University of Otago , Dunedin , New Zealand.
authors.forename: Prasad S
authors.initials: PS
authors.lastname: Nishtala
authors.affiliation: a School of Pharmacy , University of Otago , Dunedin , New Zealand.
authors.forename: Mohammed Saji
authors.initials: MS
authors.lastname: Salahudeen
authors.affiliation: b Sydney Medical School, Royal North Shore Hospital and Kolling Institute of Medical Research , University of Sydney , St Leonards , NSW , Australia.
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Hilmer
mesh_terms: D000368:Aged; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D003072:Cognition Disorders / Q000139:chemically induced* / Q000453:epidemiology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D010818:Practice Patterns, Physicians' / Q000592:standards*
chemical_list: D018680:Cholinergic Antagonists
keywords: Anticholinergic; acetylcholine; anticholinergic activity; anticholinergic adverse effect; anticholinergic burden; anticholinergic mechanism; anticholinergic medicine; anticholinergic overview; anticholinergic risk scale; antimuscarinic; muscarinic receptor; older people