So after years of doing well, first on human insulin and then on a product specifically for animals called Vetsulin, Dock's downturn this fall caused his owner's concern.
It must be his age, Mr. Friedman believed at the time. The 30-pound terrier mix was more than 13 years old. But a call from the veterinarian pointed in another possible direction - the Vetsulin given to Dock probably was defective.
"[The veterinarian] came to our home. We put him to sleep in his bed, with us petting him," Mr. Friedman said of the Dec. 2 appointment to put Dock down because of kidney failure.
Mr. Friedman has filed a lawsuit in U.S. District Court against Schering-Plough Animal Health, the New Jersey company that manufactures Vetsulin. The complaint, filed last week, alleges negligence, violation of consumer sales practice, breach of warranty, and defective product.
It also asks the court to find the complaint to be a class action lawsuit against the company on behalf of all consumers who at one time depended on the product to regulate their pets' diabetes.
"This is about getting justice for all the people who bought this product with the belief that it was going to help their dog or cat," Mr. Friedman said.
Representatives for Schering-Plough Corp. could not be reached for comment this week because the company shuts down for the holidays.
According to the lawsuit, the company sold a "contaminated or improperly manufactured veterinary diabetic medication" at least as far back as August. The complaint further alleges the company "knew or should have known for at least several months prior to the Nov. 3, 2009, warning by the FDA to stop using Vetsulin that the Vetsulin was either improperly manufactured or was contaminated."
Dr. Bob Esplin of Sylvania Vet, where Dock was a patient, said that diabetes among pets is not uncommon. In fact, he said he cares for about 50 or 60 diabetic dogs and cats at any given time in his practice.
Until recently, each was given daily doses of Vetsulin, he said.
"We got a notification from the makers of Vetsulin that there was a problem with the insulin and its ability to maintain a stable glucose level in the animal," he said. "Insulin has various rates of absorption in the body so they work over a series of time."
He added the problem with Vetsulin seemed to be that it was not being absorbed into the animals' bodies at a regular rate and was either causing a spike in sugar levels or allowing the level to get too low.
The company sent letters to veterinarians disclosing a problem, first on Nov. 6 and then on Nov. 30, according to the company's Web site. In the letters, the company told vets they "should consider starting all new diabetic patients on non-Vetsulin insulin products and transitioning existing diabetic patients to other insulins."
On Nov. 2, the Food and Drug Administration's Center for Veterinary Medicine issued an alert in conjunction with the manufacturer.
Dr. Esplin said although he was forced to change his patients' medications - many because they were reacting adversely to the product - the company did not offer a recall on the Vetsulin and so consumers were out the cost of the medications.
He ultimately switched his diabetic patients to human insulin, he said.
Vetsulin was sold by Sylvania Vet for $31.65 for 400 international units, and the cost of the necessary syringes was $40.50 for 100. How much insulin used per dose depended on the size of the animal and its level of diabetes.
The lawsuit, filed by Sandusky attorney Dennis Murray, Jr., and Toledo attorneys Rick Kerger and Steve Hartman, will be heard by Judge James Carr.
Mr. Hartman said that although the product was used by thousands of pet owners nationwide, he is not familiar with any other lawsuits filed against the company.
He said a class action lawsuit would help each of those people.
"There are so many people that use the product that the class action is the mechanism to bring all lawsuits of this type against a single party," he said.
No specified damages were listed in the lawsuit.
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