The article presents the results of treatment of 106 patients with generalized periodontitis (GP) depending on blood type. We determined the effectiveness of treatment by the frequency of detection of the main clinical symptoms (dental plaque, tartar, bleeding, tenderness, gingival hyperemia, serous-purulent discharge, periodontal pockets, pathological tooth mobility, radiological changes in the alveolar membranes) of GP. As a result of applying our proposed therapy, it was found that on day 3–5 after treatment only in patients with blood group 0 (I) of the main group the number of patients with clinical symptoms of GP was significantly less than in the control group (13.58±3.39% of patients vs. 25.69±6.42% of patients, p<0.01, respectively). At 1 month after treatment, there was a significant difference in the presence of clinical symptoms of GP in patients with blood group 0 (I) of the main and control groups (6.17±1.53% vs. 21.58±5.40%, p<0.05, respectively) and with blood group B (III) (8.33±2.08% vs. 22.22±5.56%, p<0.05, respectively). In patients with A (II) and AB (IV) blood groups, the number of patients with symptoms of GP in the study groups did not differ from each other during this follow-up period, p>0.05. After 6–12 months of study, in patients with GP, regardless of blood group, the number of patients in the main group with clinical symptoms of GP was significantly lower than in the control group, p<0.01. The improvement of clinical symptoms in patients with generalized periodontitis indicates a positive effect on the periodontal tissue the medicines we have prescribed.