Evaluation of effectiveness and safety of therapeutic regimens for dirofilariasis in dogs

Dirofilariasis caused by Dirofilaria immitis and Dirofilaria repens is a serious disease prevalent in dogs, posing significant health risks and potential zoonotic consequences for humans. This article investigates the effectiveness of various treatment protocols for canine dirofilariasis. The study aimed to assess the clinical efficacy and safety of different therapeutic approaches in treating dogs with varying stages of the disease. A total of 12 dogs were included, divided into two groups of six: a control group and an experimental group. The control group received standard therapy with melarsomine at a dose of 2.5 mg/kg administered twice on days 60 and 90. Additionally, dexamethasone was given before each injection to reduce the risk of thromboembolism. No other medications were used, and physical activity was restricted after injections. In the experimental group, an extended therapy regimen was applied: melarsomine was administered three times, supplemented with prednisolone, doxycycline, moxidectin, and other supportive drugs. This approach ensured comprehensive monitoring of the dogs' health. On days 60 and 91 of therapy, patients were closely monitored, with activity restricted to prevent complications. The study revealed no anaphylactic reactions to moxidectin in the experimental group, while side effects from doxycycline (vomiting, diarrhea, and anorexia) were effectively managed by adjusting the dosage. In the control group, side effects were more pronounced; diarrhea and vomiting required repeated dose adjustments and supportive therapy. Local reactions to melarsomine injections occurred in 67 % of the control group dogs, causing significant discomfort. Treatment results after four months showed that all dogs in the experimental group tested negative for microfilaria. After nine months, antigen tests confirmed the absence of infestation in all experimental group patients, demonstrating the high effectiveness of the comprehensive therapy. Although the control group also had negative antigen tests, clinical complications and frequent side effects indicated lower treatment efficacy. Thus, the findings confirmed the efficacy of the enhanced therapeutic regimen with triple melarsomine administration combined with doxycycline, providing reliable infestation control and minimizing complications.