Need e-mail address of Merial corp.,makers of Heartgard/dogs?

This product appears not to guarantee a pet against heartworms,and need an e-mail address to inform the makers.My pet is displaying a positive results for heartworms and has been given this product since a small pupon a monthly basis.Born on 01/08/03.Hope someone can help.

Unfortunately no heart worm medication is 100 guaranteed . That is why it is called a preventative only.I am sorry to hear your pet has contracted heart worm-did you always give it on the same day?If not the efficacy is not as great. The best way to contact the makers of Heartgard is thru the representative that deals with your veterinarian. But your vet should inform them-we would-we even inform the vaccine companies if there is a vaccine reaction in the dog.Do you live in an area where the pet should be tested twice a year and on meds all the time.At our clinic we recommended(due to environment)the pet be tested every year and if the owners do not want that we make them sign a waiver stating they understand the risks and that the product is not 100% guarantee. Not to be crude though it is like birth control 99.9% effective if given properly but nothing is 100% and they would be lying to you if they advertised it as that. Let me know about your dog though,please.