The in-use stability of Albendazole and oxytetracycline, Veterinary medicinal products commonly used in animal health and production, was investigated in suspension formulation (albendazole) or injectable formulation (Oxytetracycline), according to stability guidelines (ICH, 2003). The degradation process, if any, was monitored by an HPLC method. The change in colour using visual inspection and pH value using pH meter, was also monitored for 7 days (Oxytetracycline) and 2 months (Albendazole). Albendazole and Oxytetracycline, showed few to prominent degradation in active ingredient concentration and pH value in solution when exposed to in-use environment mimicking the storage conditions recommended by the manufacturer.  The obtained results are of interest for stability studies and/or quality control purposes of Albendazole and Oxytetracycline commercial products.