The article presents the results of clinical trials of a non-steroidal anti-inflammatory veterinary drug when administered to fattening piglets with clinical signs of musculoskeletal diseases. For the treatment of the diseases, piglets of the experimental (I) and control (II) groups received an antimicrobial drug based on the tetracycline antibiotic. The animals of the experimental group were additionally administered orally with drinking water the test non-steroidal anti-inflammatory drug based on acetylsalicylic, ascorbic and citric acids, in the recommended dosage by the manufacturer. Blood for laboratory tests was selected from piglets before and after the use of drugs. Studies of hematological and biochemical parameters were conducted according to generally accepted methods. The therapeutic efficiecy of the drug and its effect on the morphofunctional state of the body was evaluated by comparing the statistically processed data obtained before and after treatment, as well as in comparison with the indicators of animals of the control group. The analysis of hematological parameters of piglets during the experiment showed a decrease in the number of leukocytes in the animal’s blood after the use of drugs. The normalization of the leukogram was also noted by reducing the relative number of rod-nuclear neutrophils. In particular, this indicator decreased by 17.4% in group I piglets, and by 12% in group II piglets. It is noted that the clinical response to therapy was faster and more pronounced in animals, which used a non-steroidal anti-inflammatory drug in combination with an antimicrobial drug than in piglets, which were treated only by antibiotic. According to the results of biochemical studies, it was found that the content of urea in the serum of animals of both groups before the use of drugs exceeded more than 3 times the upper limit of physiological values for a given age group of piglets. After therapy with the drugs a significant decrease in the urea content in the blood serum of groups 1 and 2 animals was noted by 3.42 and 2.98 times, respectively. It is established that the activity of marker enzymes of the liver physiological state (ALT, AST) in the serum of group I piglets after complex treatment with the studied drugs was slightly reduced and was within the physiological values. In the serum of group II animals, which were treated only with antimicrobial drug, ALT activity increased by 12,0 %, and AST – by 38,6 %, compared to the initial data, and exceeded the limit of physiological values. An increase in the content of iron by 37.4 % in the blood of group I piglets, compared to the period before drug administration, was noted. No adverse reactions and negative phenomena were detected during the use of the test drug, and the drug was well tolerated. According to the clinical condition of the experimental group animals and the results of laboratory tests it was established that the use of non-steroidal anti-inflammatory drugs based on acetylsalicylic, ascorbic and citric acids simultaneously with antimicrobial therapy led to a faster improvement in the state of the musculoskeletal system. Observation during the month of the piglet’s clinical conditions confirmed the safety of the drug in the recommended dosage and method of administration in the combined treatment of inflammatory processes of the musculoskeletal system.