Global Medical Manager VIRBAC CARROS, Provence-Alpes-Cote d'Azur, France
Background: Giardia duodenalis is a commonly found gastrointestinal protozoan parasite in dogs. Metronidazole is a nitroimidazole antimicrobial with antiprotozoal actions.
Objectives: This clinical field study assessed the safety of a flavored oral suspension containing 125mg/mL of metronidazole intended to treat Giardia duodenalis infection in dogs. Animals: Client-owned dogs (n=180), naturally infected with Giardia duodenalis from European countries (Germany, Hungary, Portugal), were enrolled in the study, randomized to one of two groups and included in the safety analysis. In the metronidazole treated-group, 120 dogs received a flavored oral suspension containing 125mg/mL of metronidazole. In the control-group, 60 dogs received a vehicle flavored oral suspension (equivalent to the final formulation of the product minus metronidazole). All dogs received 0.2 mL/kg twice daily for 5 consecutive days (i.e. 25mg/kg of metronidazole twice daily).
Methods: The study was a double-masked vehicle-controlled randomized and blocked multi-center trial. A veterinary exam including hematology, biochemistry and urine analyses was performed on Day -3 (pre-administration) and Day +5 (post-administration). Owners completed daily health observations from Days 0 through 7. Safety was assessed descriptively by comparing both groups for occurence of Adverse Events (AEs).
Results: AEs (based on the VeDDRA dictionary) were tabulated in a frequency table for AEs considered related to the products (Table 1). Product-related AEs were observed in the same frequency (10%) in both groups. Diarrhoea and emesis were the most frequently reported signs in both groups. Neutropenia or elevated liver enzymes, signs expected after metronidazole administration, were observed in 0.8% of dogs in the metronidazole treated-group. Neurological signs were not observed.
Conclusion: The results demonstrated that the flavored oral suspension containing 125mg/mL of metronidazole could be administered with a measured risk of adverse reactions in dogs. The oral suspension offers an accurate weight-based dose, favoring a safer use of metronidazole.
