Pharmaceutical companies spend an average $5 billion a year pitching drugs to Americans, a practice that experts say can have negative consequences.

Since the government eased advertising restrictions on the pharmaceutical industry in 1997, billions and billions of dollars have been spent marketing prescription drugs to consumers.

“A big problem is people see ads and then may press their doctor for that particular drug,” said Consumer Reports Jamie Kopf. “And often it's not the best choice.”

In fact, a recent Consumer Reports survey reveals 20% of those regularly taking a prescription medication have requested a drug they had seen or heard advertised. The majority, 67%, say their doctor prescribed it for them.

“Another problem,” said Consumer Reports’ Dr. John Santa, “is the newest drugs being advertised may not be the safest.”

For instance, in the year 2000, Merck spent more than $160 million advertising the painkiller Vioxx. The ads ran even after concerns were raised linking Vioxx with heart problems. Merck ultimately pulled Vioxx from the market in 2004.

“People don't realize the FDA rarely reviews drug ads before they air,” said Santa. “And months, even years, can go by while safety questions are being looked into.”

Experts recommend that you talk to your doctor about what’s bothering you, but resist the urge to ask for a specific medication. Consumers should also keep in mind that older, less-advertised drugs have a longer safety and efficacy record, and often will cost less.

The United States is one of only two countries in the world that allow direct-to-consumer drug advertising. The other is New Zealand. For unbiased information, Consumer Reports says you need to look beyond the ads. One source is Consumer Reports Best Buy Drugs, which rates more than 200 top-selling medications.