The effectiveness of levamisole hydrochloride against the microfilaria of Dirofilaria immitis.

Levamisole hydrochloride was an efficient microfilaricide when used in dogs at a dosage of 10 mg/kg twice daily for 14 days. Increasing the dose rate every 3 days to 10 mg/kg twice daily and maintaining it at 10 mg/kg twice daily for a further 8 days, was also effective but a dosage of 5 mg/kg twice daily for 21 days was less effective and a dose rate of 20 mg/kg was efficient, but toxic.