Ron Chapman is waiting when a bus pulls into a Michigan parking lot at 6 a.m.

He and a group of other seniors are headed to Canada for cheaper prescription drugs.

"I feel real up," said Chapman, who has Parkinson's Disease (search). "I want to live as long as I can. And I don't want to beg but let's do it right."

With 43 million Americans riding though life without health insurance, drug drives to Canada have become life-saving staples -- especially for seniors.

It's hard to say just how many Americans are getting their prescriptions filled by Canadians. Pharmacy groups estimate that it's about 3 to 4 million prescriptions (search) annually.

The Canadian government negotiates its drug prices and with the cheaper dollar, medicine averages about half the price as the same drugs sold in the United States.

"The prescription I'm picking up today would have cost me $1,200 in the United States versus $500 here," said Gil Groehn, a Canadian customer.

Diagnosed with prostate cancer, Groehn said exorbitant drug prices have forced seniors north.

"Myself and other seniors are being virtually raped," he said.

But U.S. drugmakers maintain the assertion is not true. Pharmaceutical officials say price controls keep prescription costs down in Canada but that research and development drive prices up in the United States.

Eli Lilly (search) is one of several U.S. drug makers now reducing pill supplies to Canada to ensure there's not a surplus to sell to Americans at cheaper prices.

"It takes about $800 million to develop and launch the product and only one of three products that actually make it to market, recoup the development cost," said Rob Smith, a spokesman for Eli Lilly.

Illinois Gov. Rod Blagojevich has unveiled a plan to make his state the first to buy prescription drugs from Canada, a move he said would save taxpayers $90 million.

"There's a pricing structure that's essentially been fixed for a long time that the big pharmaceutical companies are interested in protecting," the Democratic governor said.

Other governors have said they'll challenge the federal Food and Drug Administration (search) for the right to do the same.

"We're concerned about the safety implications of any state or locality bringing in foreign drugs and about the legal implications if jurisdictions such as that were to do such a thing," said the FDA's William Hubbard.

Congress is battling over how to reform Medicare and whether to allow foreign prescription imports.  

For Ron Chapman, who takes 20 pills a day at a cost of $1,500 a month, the decision about drugs is an easy one: he can't afford not to go to Canada even though it pains him.

"I'm an American," Chapman said, his voice quivering. "I'm not a liberal. I'm not a conservative. But I am an American."