The article considers a clinical case of treatment of one of the variants of nonspecific back pain – sacroiliac joint syndrome. In this case, we tried to demonstrate the importance of timely and accurate determination of the cause of dorsalgia using currently available tools: medical scales, X-ray and MRI examination, diagnostic drug blockade of the pain zone. A scrupulous analysis of complaints, anamnesis and clinical manifestations of the patient, a differential diagnosis with a number of diseases with a similar clinical picture, as well as the choice of treatment tactics based on federal clinical recommendations for the treatment of patients with nonspecific back pain made it possible to quickly determine the diagnosis and cope with the pain syndrome. Therapy with the inclusion of medications, physiotherapy, manual therapy, post-isometric relaxation, physical therapy, posture correction allowed the patient to stop the pain syndrome and return to an active lifestyle. Dexketoprofen (Dexalgin®) was prescribed to relieve the pain syndrome. Optimization of the method of administration of the drug is a step-by-step scheme for prescribing dexketoprofen: parenteral administration of 2 injections (50 mg) intramuscularly daily for 2 days, then transfer to oral Dexalgin intake – 25 mg 2 times a day for 3 days under the guise of proton pump inhibitors – Esomeprazole 40 mg 1 time a day, the use of a patch with a local anesthetic, vitamins of group B – 12 days, therapeutic and diagnostic drug blockades – contributed to a significant reduction in the intensity of the pain syndrome and allowed to prevent its transformation into a chronic process. As a result of the use of complex, pathogenetically based therapy, a rapid positive therapeutic effect was achieved.