title: Safety profile of tolterodine as used in general practice in England: results of prescription-event monitoring.
abstract: BACKGROUND
  Unstable bladder symptoms are a common problem in general practice. Drug therapy with anticholinergic drugs is frequently used in the management of this condition. However such drugs are associated with a high incidence of anticholinergic adverse effects. Tolterodine is a competitive anticholinergic agent, selective for the bladder as opposed to the salivary glands.
  
  
  OBJECTIVE
  To monitor the safety of tolterodine as used in general practice patients in England for the treatment of urinary frequency, urgency and incontinence.
  
  
  METHODS
  Prospective observational cohort study.
  
  
  METHODS
  14,526 patients [mean age 62.7 (SD 16.4) years; 68.6% female].
  
  
  METHODS
  Patients prescribed tolterodine in general practice, soon after the release of the drug in the UK, were followed up for a minimum of 6 months using the technique of prescription-event monitoring (PEM).
  
  
  RESULTS
  The most common adverse events reported were dry mouth, headache, malaise, constipation, dyspepsia, nausea and vomiting and pain in abdomen. We identified some uncommon events as possible adverse drug reactions--notably hallucinations, tachycardia and palpitations. The prevalence of these events was compared with that in patient cohorts for other drugs on the PEM database. The age- and sex-adjusted relative risk of hallucinations on tolterodine compared with 10 drugs of other therapeutic classes, and with terodiline, another drug indicated for bladder instability, was 4.85 [95% confidence interval (CI) 2.72 to 8.66] and 1.25 (95% CI 0.62 to 2.53), respectively. There was no significant difference for tachycardia/palpitation in this comparison.
  
  
  CONCLUSIONS
  Tolterodine is well tolerated in general practice at the recommended daily dose. Hallucinations, tachycardia and palpitations are infrequently associated with the drug.
authors.affiliation: Drug Safety Research Unit, Southampton, England.
authors.forename: D
authors.initials: D
authors.lastname: Layton
authors.forename: G L
authors.initials: GL
authors.lastname: Pearce
authors.forename: S A
authors.initials: SA
authors.lastname: Shakir
mesh_terms: D001559:Benzhydryl Compounds / Q000009:adverse effects / Q000627:therapeutic use*; D015331:Cohort Studies; D003408:Cresols / Q000009:adverse effects / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000379:methods*; D004739:England; D005194:Family Practice; D005260:Female; D006212:Hallucinations / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D010665:Phenylpropanolamine; D011795:Surveys and Questionnaires; D013610:Tachycardia / Q000139:chemically induced; D000068737:Tolterodine Tartrate; D014570:Urologic Diseases / Q000188:drug therapy*
chemical_list: D001559:Benzhydryl Compounds; D003408:Cresols; D018727:Muscarinic Antagonists; D010665:Phenylpropanolamine; D000068737:Tolterodine Tartrate