Virbac has expanded its voluntary recall of Iverhart Plus Flavored Chewables following its initial recall notice in April 2013. 

According to PetMD, additional specific lots of the heartworm preventive are being recalled because they might not fully protect dogs in the upper third of each weight range.

PetMD cited a letter distributed by Virbac saying that 14 lots of Iverhart Plus Flavored Chewables were below Ivermectin potency levels prior to their expiration. Another 17 lots are being recalled out of caution even though they remain within specification.

Virbac is recalling the following lot numbers for each weight range:

Small dogs (up to 25 pounds)

• 120092
• 120397
• 120398
• 120798

Medium dogs (26-50 pounds)

• 120090
• 120301
• 120378
• 120450
• 121282

Large dogs (51-100 pounds)

• 120091
• 120127
• 120195
• 120207
• 120256
• 120289
• 120300
• 120305
• 120306
• 120377
• 120379
• 120434
• 120440
• 120464
• 120651
• 120658
• 120678
• 120831
• 121110
• 121150
• 121283
• 121386 

Consumer information

Virbac directs consumers who have questions about the recall to contact Virbac Technical Services at 1-800-338-3659, ext. 3052.