title: Experimental determination of a subantimicrobial dosage of doxycycline hyclate for treatment of periodontitis in Beagles.
abstract: OBJECTIVE
  To identify a subantimicrobial dose of doxycycline hyclate (SDD) and for the treatment of periodontitis in dogs.
  
  
  METHODS
  20 healthy Beagles for measurement of serum doxycycline concentration and 15 Beagles with periodontitis for evaluation of the efficacy of the SDD.
  
  
  METHODS
  5 dogs each received doxycycline hyclate PO at a dose of 1, 2, 3, or 5 mg/kg. Blood samples were collected before and after administration, and serum concentrations of doxycycline were measured via high-performance liquid chromatography. Mean serum doxycycline concentrations were calculated, and SDDs were identified. In a separate trial, the identified SDDs (1 or 2 mg/kg) were administered PO once a day for 1 month to dogs with periodontitis (n = 5/group) and a control group (5) was fed vehicle only during the same period. Degree of gingival attachment and bleeding on probing (present or absent) were recorded. Gingival samples were collected before and after the 1-month period from the same anatomic sites. Degree of matrix metalloproteinase inhibition in gingival samples was determined via gelatin zymography and compared among treatment groups.
  
  
  RESULTS
  Mean serum doxycycline concentrations in healthy dogs that received 1 or 2 mg of doxycycline/kg were consistently significantly lower than the minimal inhibitory doxycycline concentration for treatment of periodontitis throughout the 24-hour posttreatment period. Zymographic intensities were lower in dogs given 1 and 2 mg/kg than in the control dogs, and the degree of gingival attachment and bleeding significantly improved in dogs given 2 mg/kg, compared with in the control dogs and dogs given 1 mg of doxycycline/kg.
  
  
  CONCLUSIONS
  A doxycycline dosage of 2 mg/kg daily appeared to be an appropriate subantimicrobial regimen for dogs with periodontitis. Furthermore, this dosage may be suitable for long-term treatment of gelatinolytic inflammatory diseases such as periodontitis in this species.
authors.affiliation: Department of Veterinary Surgery and Ophthalmology, College of Veterinary Medicine and BK21 Program for Veterinary Science, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul, Korea.
authors.forename: Se Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Soohee
authors.initials: S
authors.lastname: Kim
authors.forename: Manbok
authors.initials: M
authors.lastname: Jeong
authors.forename: Yesran
authors.initials: Y
authors.lastname: Lee
authors.forename: Jeong Taek
authors.initials: JT
authors.lastname: Ahn
authors.forename: Young Woo
authors.initials: YW
authors.lastname: Park
authors.forename: Jae Sang
authors.initials: JS
authors.lastname: Ahn
authors.forename: Euiri
authors.initials: E
authors.lastname: Lee
authors.forename: Doug-Young
authors.initials: DY
authors.lastname: Ryu
authors.forename: Kangmoon
authors.initials: K
authors.lastname: Seo
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy / Q000662:veterinary*; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004318:Doxycycline / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D010518:Periodontitis / Q000188:drug therapy / Q000662:veterinary*
chemical_list: D000900:Anti-Bacterial Agents; D004318:Doxycycline