title: [Viscosity changes in thickened water due to the addition of highly prescribed drugs in geriatrics].
abstract: BACKGROUND
  Dysphagia is a swallowing disorder with a high incidence in the geriatric patient related with an increased risk for undernutrition and pneumonia due to bronchial aspiration. In this condition, it is usual to add commercial thickeners in liquids, as well as the addition of drugs in this mixture to improve their administration. However, there are no studies regarding the possible change in viscosity produced by their addition.
  
  
  OBJECTIVE
  To assess the change in viscosity of water thickened with commercial products by adding the drugs frequently used in elderly patients.
  
  
  METHODS
  Samples of water mixed with the commercial thickener Resource (modified corn starch) or Nutilis (modified corn starch, maltodextrin, and gums: tara, xhantan, and guar) to achieve an intermediate consistence as "honey". The viscosity of these samples was measured as well as for similar samples to which one of the following drugs was added: galantamine, rivastigmin, ciprofloxacin, cholecalciferol, memantine, fosfomycin, calcium, and amoxicillin/clavulanic acid.
  
  
  RESULTS
  In the samples with Resource thickener we observed decreased viscosity by adding galantamine, memantine, fosfomycin or calcium, and increased viscosity with amoxicillin/clavulanic acid. The viscosity of the samples with Nutilis® decreased with galantamine, rivastigmine, amoxicillin/clavulanic acid, fosfomycin and calcium.
  
  
  CONCLUSIONS
  The viscosity of water with commercial thickeners may be affected by some drugs or their preservatives, which may influence the swallowing capability. It is recommended to perform further in vitro and in vivo studies in order to adjust these formulations if necessary.
authors.affiliation: Servicio de Farmacia, Hospital de Santa Creu i Sant Pau, Barcelona, España. ngarinescriva@gmail.com
authors.forename: N
authors.initials: N
authors.lastname: Garin
authors.forename: J T
authors.initials: JT
authors.lastname: de Pourcq
authors.forename: D
authors.initials: D
authors.lastname: Cardona
authors.forename: R
authors.initials: R
authors.lastname: Martín-Venegas
authors.forename: I
authors.initials: I
authors.lastname: Gich
authors.forename: J
authors.initials: J
authors.lastname: Cardenete
authors.forename: M A
authors.initials: MA
authors.lastname: Mangues
mesh_terms: D000284:Administration, Oral; D000368:Aged; D004339:Drug Compounding; D005079:Excipients; D005260:Female; D006801:Humans; D008297:Male; D055553:Prescription Drugs / Q000008:administration & dosage* / Q000737:chemistry*; D013213:Starch; D014783:Viscosity; D014867:Water / Q000737:chemistry*
chemical_list: D005079:Excipients; D055553:Prescription Drugs; D014867:Water; D013213:Starch