title: How much antibiotic suspension is enough?
abstract: OBJECTIVE
  Pilot data suggest that inadequate antibiotic volumes are often dispensed. Study goals were to determine the frequency of inadequate antibiotic volumes dispensed by local pharmacies, develop prescription-writing guidelines to ensure that adequate antibiotic suspension volumes are dispensed, and document the adequacy of verbal/written counseling pharmacists provide.
  
  
  METHODS
  Sixty-one local pharmacies filled prescriptions for penicillin potassium (PCN; 250 mg/5 mL [5 mL orally 3 times daily for 10 days]) and Bactrim (trimethoprim-sulfamethoxazole [TMP-SMX] 5 mL orally twice daily for 10 days). The prescriptions noted only to "dispense a 10-day supply. " Volumes were measured first as total amount dispensed and then into total doses dispensed. Written/verbal instructions were documented.
  
  
  RESULTS
  The volume of PCN dispensed was 195 +/- 25 mL (range: 105-222 mL) for an average of 29.4 doses, where 30 doses were needed. TMP-SMX dispensed had a volume of 107 +/- 5 mL (range: 98-120 mL) resulting in an average of 16.5 doses, where 20 doses were needed. Twenty pharmacies (33%) did not dispense a measuring device. Verbal counseling by the pharmacist and written instructions were not uniformly given.
  
  
  CONCLUSIONS
  We suggest calculating the actual volume needed plus an additional 10% to 30% of volume (depending on the viscosity). The prescription should also request a medication-measuring/administering device. Patient counseling and instruction should be expanded.
authors.affiliation: Department of Pediatrics, University of Iowa College of Medicine, Iowa City, IA 52242-1083, USA. lois-dusdieker@uiowa.edu
authors.forename: L B
authors.initials: LB
authors.lastname: Dusdieker
authors.forename: J R
authors.initials: JR
authors.lastname: Murph
authors.forename: G
authors.initials: G
authors.lastname: Milavetz
mesh_terms: D000284:Administration, Oral; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D000890:Anti-Infective Agents; D011307:Drug Prescriptions / Q000592:standards; D016568:Drugs, Generic; D006801:Humans; D010353:Patient Education as Topic; D010400:Penicillin G / Q000008:administration & dosage; D010604:Pharmacy / Q000592:standards; D010865:Pilot Projects; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000008:administration & dosage
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D016568:Drugs, Generic; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D010400:Penicillin G