Resistance to Ivermectin

Ivermectin is an anti-parasite medication that can be used to treat pets such as dogs and cats as well as farm animals including sheep, goats and cattle. Some parasites are showing signs of being resistant to ivermectin, which was introduced in the 1980s.

  1. Ivermectin

    • Ivermectin is effective against a wide range of pests, including mites, intestinal worms and some lice, according to Mar Vista Animal Medical Center in Los Angeles.

    Resistance

    • Parasites that are targeted by ivermectin must either develop resistance to the medication or be eliminated every time the medication is used, according to "Georgis' Parasitology for Veterinarians."

    Issues

    • Parasites found in sheep and goats in the United States and around the world are beginning to show signs of resistance to ivermectin. The medication does not eliminate them when delivered in the usual dosage levels.

    Solutions

    • Increased dosages can overcome a parasite's resistance to ivermectin. If increasing the dosage is not feasible, then switching to a different anti-parasite medication will eliminate the pest.

    Considerations

    • On occasion, a parasite will appear to be resistant to ivermectin when the medication is delivered incorrectly, or when it is used to treat a pest against which it is ineffective.