title: Pharmacokinetics of rizatriptan in healthy elderly subjects.
abstract: OBJECTIVE
  Rizatriptan is a serotonin 5-HT1B/1D receptor agonist for acute treatment of migraine. Its pharmacokinetics were assessed in healthy elderly males and females receiving a single 10 mg tablet oral dose. The pharmacokinetic data (AUC(0-infinity) and Cmax) for the elderly in this study were compared with historical data from previous studies for healthy young adults (n = 65).
  
  
  METHODS
  In a double-blind, parallel, placebo-controlled study, healthy elderly female and male subjects aged 65 or older (n = 8 each) received a single oral dose of 10 mg rizatriptan. Plasma and urine concentrations of drug were determined by HPLC with tandem mass spectrometry detection at several collection time points or intervals starting at predose and postdose over 24 h.
  
  
  RESULTS
  In elderly subjects, the geometric mean values for AUC(0-infinity) and Cmax were 77.7 ng/h/ml and 21.9 ng/ml; the average values for tmax, half-life (t 1/2), renal clearance (Clr), and percent urinary excretion of dose (Ue) were 1.2 h, 1.8 h, 197 ml/min and 9.3%, respectively. The AUC(0-infinity) and Cmax of rizatriptan were similar in elderly and young subjects. The geometric mean AUC ratio of elderly to young was 0.96 with 90% confidence interval (0.83, 1.11), p > 0.25. The geometric mean Cmax ratio was 0.89 with 90% confidence interval (0.72, 109), p > 0.25. No significant pharmacokinetic differences were observed between elderly males and females.
  
  
  CONCLUSIONS
  The plasma pharmacokinetics of rizatriptan appear to be similar in the elderly and young. In the elderly, the pharmacokinetics of rizatriptan do not appear to differ between male and female to a clinically significant extent.
authors.affiliation: Merck Research Laboratories, West Point, PA 19486, USA. don_musson@merck.com
authors.forename: D G
authors.initials: DG
authors.lastname: Musson
authors.forename: K L
authors.initials: KL
authors.lastname: Birk
authors.forename: D L
authors.initials: DL
authors.lastname: Panebianco
authors.forename: K D
authors.initials: KD
authors.lastname: Gagliano
authors.forename: J D
authors.initials: JD
authors.lastname: Rogers
authors.forename: M R
authors.initials: MR
authors.lastname: Goldberg
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism*; D000704:Analysis of Variance; D019540:Area Under Curve; D002851:Chromatography, High Pressure Liquid; D004311:Double-Blind Method; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D017366:Serotonin Receptor Agonists / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D014230:Triazoles / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D014363:Tryptamines
chemical_list: D017366:Serotonin Receptor Agonists; D014230:Triazoles; D014363:Tryptamines; C093622:rizatriptan