title: Therapeutic drug monitoring of gentamicin: evaluation of five nomograms for initial dosing at Al-Amiri Hospital in Kuwait.
abstract: OBJECTIVE
  To compare five published nomograms (Thomson guidelines, Mawer nomogram, rule of eights, Hull-Sarubbi table and Dettli method) for calculating the initial gentamicin dosage regimen in a Kuwaiti population.
  
  
  METHODS
  Based on measured peak and trough gentamicin concentrations, the elimination rate constant and volume of distribution of gentamicin were calculated for each patient (n = 56), using a modified two-point Sawchuk-Zaske method. The calculated individual set of pharmacokinetic parameters and the initial dose regimen recommended by each of the five methods were used to predict the steady-state peak and trough of gentamicin concentrations.
  
  
  RESULTS
  The Thomson guidelines produced consistent results in predicting gentamicin concentrations within the target ranges of peak plus trough, peak only and trough only (63, 75 and 75%, respectively). The Mawer nomogram, Hull-Sarubbi table and Dettli methods achieved similar percentages of patients (46-50%) within the target ranges (5-10 mg x l(-1) for peak and 0.5-2 for trough), whereas empirical dosing and the rule of eights showed the lowest percentages of patients within the peak plus trough target range (25 and 37%, respectively). However, with respect to the underdosing target range (predicted concentration <5 mg x l(-1)), the Thomson guidelines showed that 21% of patients were underdosed.
  
  
  CONCLUSIONS
  The results show that a large number of patients (37-63%) were outside the target ranges in all initial gentamicin dosing methods evaluated in this study. Therefore, serum concentration measurement can be advised to assist in the optimization of gentamicin dose selection.
authors: Department of Pharmacy, Al-Amiri Hospital, Ministry of Health, Kuwait. yousefl@hsc.edu.kw
authors: Yousef
authors: Y
authors: Al-Lanqawi
authors: Phillip
authors: P
authors: Capps
authors: Mohamed
authors: M
authors: Abdel-hamid
authors: Kefaya
authors: K
authors: Abulmalek
authors: Dotun
authors: D
authors: Phillips
authors: Kamal
authors: K
authors: Matar
authors: Prem
authors: P
authors: Sharma
authors: Anil
authors: A
authors: Thusu
mesh_terms: D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000378:metabolism; D003404:Creatinine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D005839:Gentamicins / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use*; D006801:Humans; D007730:Kuwait; D008297:Male; D008875:Middle Aged; D049451:Nomograms; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D003404:Creatinine