* Arsenicals - '''Thiacetarsamide''' has been used to treat the adult heartworm but is very toxic. It is hepatotoxic, nephrotoxic and will cause necrosis if not injected directly into the vein. '''Melarsomine''' is a new drug that has just become available.
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* '''Arsenicals''' - '''Thiacetarsamide''' has been used to treat the adult heartworm but is very toxic. It is hepatotoxic, nephrotoxic and will cause necrosis if not injected directly into the vein. '''Melarsomine''' is a new drug that has just become available.