From Dog

Thiacetarsamide is an organic trivalent arsenical drug (containing 17.8% arsenic) used for treatment of canine heartworm disease caused by Dirofilaria immitis.

Efficacy of this drug is approximately 50 - 75% adulticidal[1], but side-effects, particularly thromboembolism warrant consideration before undertaking adulticidal therapy with this drug.

Recommended dose rate is 12 mg/4.5 kg given as an intravenous injection daily for 3 days.

Caution with injections should be given to limit perivasacular necrosis due to drug-induced vasculitis.


  1. Rawlings CA et al (1993) Pulmonary thromboembolism and hypertension after thiacetarsamide vs melarsomine dihydrochloride treatment of Dirofilaria immitis infection in dogs. Am J Vet Res 54(6):920-925