Purpose - to develop a simple, constellational clinical system for assessing the severity of the course of acute tonsillopharyngitis (ATP) in children to optimize etiotropic treatment by reducing unreasonable antibiotic therapy. Materials and methods. We observed 102 children with ATP. A developed scale for assessing the severity of the course of ATP was used to monitor children. Evaluation of clinical symptoms with calculation of points was carried out daily, during 7 days of inpatient treatment. For the purpose of comparative analysis, as a "golden" standard, we used the assessment of symptoms of ATP according to the McIssac scale. A rapid test manufactured by Dectra Pharm (France) - Streptatest was used to verify the etiology of ATP caused by group A β-hemolytic streptococcus. Results. Indicators of the diagnostic value of the developed severity scale in establishing the streptococcal etiology of ATP (score ≥45 points) exceed the McIsaac scale score (sum of points ≥4), in particular, sensitivity - 85.7% (vs. 77.1%), specificity - 76.1% (against 31.3%), positive predicted value 78.2% (against 52.8%), negative predicted value - 84.2% (against 57.7%). The total score on the severity scale, which is 45 points or more, significantly increases the risk of ATP caused by β-hemolytic streptococcus of group A: odds ratio (OR) - 19.0, relative risk (RR) - 4.94, absolute risk (AR) - 0.62, which can be considered an indication for appointment of antibacterial therapy for hospitalized patients. A total score of ≥35 points on the 3rd day of inpatient treatment, is associated with a statistically significant risk of the absence of streptococcal infection of the oropharynx, and therefore is an indication to cancel the use of antibiotics: OR - 2.3, RR - 1.45, AR - 0.2. Conclusions. The developed scale of the severity of the course of ATP allows to extend the first 3 days to statistically reliably detect a more pronounced inflammatory process caused by Str. Pyogenes and optimize tactics of etiotropic therapy. This constellation system is especially useful in conditions of limited resources and the impossibility of using rapid Streptatests, when obtaining dubious or contradictory results of the McIsaac scale assessment, or when applying the strategy of delayed appointment of antimicrobial agents. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the institution mentioned in the paper. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.