The shortage of Immiticide (melarsomine dihydrochloride) that has persisted in the U.S. since 2011 continues to affect the nation's veterinarians, but the FDA is making an effort to make the drug available in the cases of pets dealing with severe heartworm infection.

The FDA said it will continue to allow Merial, the drug's manufacturer, to import a limited supply of the heartworm treatment from the company's European supplier. The imported medicine will supplement the small amount of U.S.-manufactured Immiticide that is available, the agency said.

Despite the FDA's measures to aid the situation, there is still not enough Immiticide to satisfy the country's demand on a large scale. The agency and Merial are both asking veterinarians to use the available supply sparingly and only on dogs that have the most immediate need.

Instructions for obtaining Immiticide

According to the FDA, veterinarians can only obtain Immiticide from Merial through a restricted distribution program. The drug is not available for purchase through Merial's distributors.

The agency advises veterinarians to contact Merial Customer Care at 1-888-MERIAL-1 (1-888-637-4251) to learn more about obtaining the drug.

Veterinarians who obtain the drug should note that domestic and European Immiticide products are not the same and have different expiry lengths, so extra attention should be given to the expiration dates, the FDA said.

Additional information about the shortage

You can find more information about how Merial is handling the Immiticide shortage in the company's Nov. 1 "Dear Doctor" letter to U.S. veterinarians.