Robert Jarvik, the inventor of the artificial heart, is at the center of a congressional investigation into his credentials and his role as pitchman for the top-selling cholesterol-lowering drug Lipitor.
In the commercials, Jarvik says, "Lipitor is one of the most researched medicines. I'm glad I take Lipitor, as a doctor, and a dad."
Despite his famous medical breakthrough, Jarvik ended his training after medical school, instead of completing a medical internship. He can't legally prescribe medicine to anyone and he is not licensed to practice medicine.
"I am a medical scientist not a practical physician," he said on "Good Morning America" today. "I think it's very upfront. I am a doctor. I have long experience with heart disease."
Jarvik, who said he was aware of the drug and used it before he became its pitchman, said he believes the real issue isn't about him or his role in the ads.
His goal is to disseminate the message of preventive medicine in relation to heart disease.
"Our ad campaign with Pfizer is an educational," he said. "Lipitor is the most widely prescribed drug in the country. For every prescription there is a doctor writing it. It's a huge vote of confidence."
Michigan Reps. John Dingell and Bart Stupak, both Democrats, sent a letter to drug company Pfizer last week, questioning Jarvik's credibility.
"Is he entitled to appear here and prescribe or give the impression he can prescribe prescription pharmaceuticals for patients?" Dingell said. "I think the law in every state says, no he's not, because he can't prescribe medicine in any state we can find."
Pfizer released a statement, saying, "Dr. Jarvik is a respected health-care professional and heart expert. The advertising advises consumers to speak to their physicians about their heart health."
Congress has also asked for records proving Jarvik took the medication, as he states in the ads.
"We're looking to see if there is wrongdoing but also we're looking to see if the law needs to be changed to give us a better level of protection for the consumers," Dingell said.
There has been a barrage of pharmaceutical advertising in the last decade. Last year alone, drug companies spent $4.8 billion on advertising.
Jarvik certainly isn't the first celebrity pitchman for a drug. Sen. Bob Dole famously shilled for Viagra, and actress Sally Field appears in commercials for the osteoporosis medication Bonvia.
Critics say using a celebrity physician may cross an ethical line.
"To have a celebrity physician associated with cardiac health telling me I need Lipitor and when it costs significantly more than a generic alternative that might be appropriate for me— that's a physician motivated by a paycheck, not by patient health," said Katie Watson, of the Medical Humanities & Bioethics Program at Northwestern University.
Jarvik has maintained that he's never cast himself as a practicing doctor.
"There is a clear matter that I am not a practicing physician, I have never been a practitioner, everybody has known for decades. I'm a developer of the technology," Jarvik said.
He added that while what he has earned for the ads is not comparable to what a celebrity endorsement would garner, the amount he receives would be "considered a lot by most people."