All Pets Veterinary Clinic
On September 3, 2004, Fort Dodge voluntarily complied with the FDA's request to temporarily
stop production of ProHeart 6 injectable heartworm medication. In addition, all current
supplies of Proheart have been recalled.
During the recall, the FDA will review safety data on ProHeart. There have been over 5000
reports of side effects ranging from mild swelling at the injection site to severe autoimmune
related illnesses, bleeding, and liver disease. Some of these severe illnesses have resulted
While these cases are important their significance is not fully understood at this time. The
data indicates that the overall side effect rate is one half of one percent (0.05%) for the over
18 million doses that have been sold. For bleeding and autoimmune reactions the rate of
occurance is one in 31,000 doses. This is less than the rate that would be expected in the
normal United States canine population. In addition, the average age of dogs experiencing
liver related side effects is within the range that is reported for the general canine population.
Therefore, the question remains, is ProHeart causing these side effects or would the affected
dogs have experienced these illnesses regardless of ProHeart?
At All Pets Veterinary Clinic, we have been using ProHeart since it was first launched over
two years ago. We have had one reported side effect--a swelling at the site of injection.
Within 24 hours, the swelling was gone. We believe in the benefits of ProHeart 6 and stand
behind this product. All medications have side effects for some individuals. Overall, we
feel that the small risk of serious side effects is less than the risks associated with
heartworm disease. We have stopped using ProHeart during the recall and will resume if the
FDA reapproves this drug. If your dog is currently on ProHeart we recommend restarting
an oral heartworm preventative (Interceptor, Sentinel, or Heartguard) or topical heartworm
preventative (Revolution) when your dog would be due for it's next ProHeart injection.
There is no need to start an oral or topical heartworm medication earlier as the effectiveness
of ProHeart is not in question. As always, you should continue to monitor the health
status of your pet. If you have any questions or concerns, please do not hesitate to contact
The information provided is for educational purposes only and is not
intended to take the place of your regular veterinarian. Please do not hesitate
to contact your regular veterinarian if you have questions regarding your pet.
Karen Blakeley, DVM, MPH
11 September 2004