Dr. Ed Greeno says it hasn't happened yet.

But the cancer specialist at the University of Minnesota said he lives in fear of having to tell a patient: "We can't get the best drug, so we have to settle for something that's not as good."

On Wednesday, Greeno joined Sen. Amy Klobuchar, D-Minn., at a news conference to voice concern about a growing shortage of prescription drugs, including morphine and cisplatin, a widely used cancer drug.

According to Klobuchar, 150 drugs are now considered in short supply in the United States -- twice as many as five years ago. As a result, she said, she plans to introduce legislation to speed up the availability of substitutes, including comparable drugs from other countries.

"Fortunately in Minnesota, we haven't had any serious adverse results yet," she said at the news conference at Fairview Southdale Hospital in Edina. "But there's absolutely no doubt that there's been an increasing shortage of drugs."

In the past few weeks, hospitals and clinics in Minnesota and around the country have had to scramble for adequate supplies of key medications.

The shortages have been blamed, in part, on production problems as well as decisions by drug manufacturers to stop making inexpensive generic drugs. In addition, a California plant that manufactures cisplatin was shut down by federal authorities earlier this year because of concerns about bacterial contamination.

Klobuchar said her legislation, which she hopes will draw bipartisan support, would require drug manufacturers to warn the Food and Drug Administration of impending shortages, and to ease rules on importing drugs from Canada and other countries.

"I don't think anyone thinks the government can go into a drug company and force them to make a certain drug," Klobuchar said. But she said advance warning would give the FDA a chance to respond more effectively "and cut through red tape to get these drugs going again."

At the same time, Klobuchar said she wants to ease restrictions on importing foreign drugs from countries such as Canada, especially when medications are in short supply here. Foreign drugs cannot be imported legally into the U.S., although the FDA can allow exceptions in rare cases.

The pharmaceutical industry has long opposed the idea of allowing drug imports, saying it could open the door to counterfeit or dangerous drugs. But Jennifer Wall, a spokeswoman for the Pharmaceutical Research and Manufacturers of America, had no immediate reaction to Klobuchar's proposal. "We'd have to thoroughly review her legislation to really comment," she said.

Greeno, the oncologist, said it's easier to find replacements for some drugs than others. "In most cases, there's always a substitute," he said, but it may not be equally effective. He noted that cisplatin, one of the drugs in short supply, has an 85 percent success rate treating testicular cancer; using a substitute, carboplatin, drops the success rate to 75 percent.

It hasn't come to that yet, he said, in part because hospitals and clinics have been trading medications as needed. "We're always scrambling to make sure that we have enough on hand to treat the patients we have," he said.

Darcy Malard-Johnson, a pharmacist at the University of Minnesota's cancer clinic, said 13 of the 150 drugs on the current shortage list are cancer drugs. Most have been around for years, she said, and that may be one of the problems. Because they're generic, they're not as profitable to make or sell as newer drugs. And there's no way of knowing when a company will simply decide to stop making it.

Klobuchar said the legislation would help the FDA protect patients from critical shortages. "This shouldn't be happening in our country," she said.

Maura Lerner • 612-673-7384