Six lots of Iverhart Plus Flavored Chewables, a heartworm preventive, have been recalled because of a stability issue involving the medication's active ingredient ivermectin, the American Veterinary Medical Association reported this week.
The manufacturer, Virbac Animal Health of Fort Worth, Texas, did not issue a public recall notice. A spokesperson could not be reached to comment.
A selected amount of Iverhart was recalled:
Iverhart Plus, a generic equivalent to Merial Ltd.'s Heartgard Plus, is formulated for the prevention of heartworm disease and for the treatment and control of roundworms and hookworms.
Stability concerns led Virbac to recall a single lot of Iverhart Max Chewable Tablets in April 2012. A lack of stability can reduce a medication's efficacy.
Veterinarians or pet owners who have questions may contact Virbac Technical Services at 800-338-3659, ext. 3052.