To control and prevent Ctenocephalides in animals, many drugs of different chemical groups and manufacturers have been proposed, which do not always have a high therapeutic and prophylactic effect. This forces scientists and experts in many countries worldwide to evaluate the effectiveness of available drugs against Ctenocephalides spp. and the development of optimal timing of their use for ctenocephalidosis in dogs. The study aimed to establish the therapeutic efficacy of various modern remedies for ctenocephalidosis in dogs. For this purpose, drugs with different active substances and methods of application were tested: sarolaner (oral tablets “Simparica”), fipronil (drops and collar “Insektostop”), as well as a combination drug: fipronil + S-methoprene (drops “Fipren”). It was found that the most effective insecticides against fleas species Ctenocephalides felis and Ct. canis, parasitic in dogs, were found in oral tablets “Simparica” and drops “Fipren”. Their extensefficacy and intensefficacy on the 30th day of the experiment was 100.0 %. The effectiveness of the “Insektostop” collar was low. Thus, after 24 h, its extens- and intensefficacy concerning Ct. felis was 0 and 55.25 %, relative to Ct. canis – 33.33 and 75.00 %, respectively. After 72 h, the efficiency increased slightly relative to Ct. felis 16.67 and 66.60 %, and relative to Ct. canis – 100.00 %, respectively. On the 14th day of the experiment, the efficiency indicators were at the level: relative to Ct. felis – 0 and 39.77 %, relative to Ct. canis – 50.00 and 58.59 %, and at 30 th days – 16.67 and 36.74 % (relative to Ct. felis), 66.67 and 43.27 % (relative to Ct. canis), respectively. After application of “Insektostop” drops after 24 h, the drug's effectiveness was high (100.0 %) against fleas of the Ct. canis. At the same time, the drops were not effective against Ct. felis – 0 and 47.36 %. After 72 h, the efficacy values were relative to Ct. felis – 16.67 and 69.3 %, and relative to Ct. canis – 50.00 and 76.54 %, respectively. During 14–30 days of the experiment, the indicators of extens- and intensefficacy gradually decreased from 33.33 to 16.67 % and from 65.08 to 48.09 % relative to Ct. felis. Regarding Ct., canis extensefficacy remained at 83.33 %, and intensefficacy decreased from 58.59 to 51.38 %. The research results allow us to recommend highly effective drugs in the control and prevention of Ctenocephalides in dogs caused by fleas of Ctenocephalides felis and Ct. canis.