Ivermectin DOES come in an injectible form and has an "off label" (aka extra label) use to kill the microfilaria in heartworm disease.
How Ivermectin Is Supplied Ivermectin is available in 10 mg/ml and 2.7 mg/ml injectable form; 0.153 percent and 1.87 percent paste form; 10 mg/ml liquid oral form and 68 mcg, 136 mcg and 272 mcg tablets.
Ivermectin can be used in an extra-label manner to kill microfilaria (microscopic offspring) in heartworm infected dogs. Ivermectin (Ivomec®, Heartgard®)