WASHINGTON - Would consumers get the same warm, fuzzy message from a drug ad that promised to lift their mood if it also urged them to report side effects such as suicidal thoughts and diarrhea?

Under a proposal regulators will consider today, that buyer-be-vigilant message would have to accompany the rosy messages of pharmaceutical promotions.

The Food and Drug Administration is considering requiring TV drug advertisements to carry a toll-free number where patients can report serious problems with their medication. The FDA will consult a panel of outside communication experts about whether displaying that language could distract viewers from other important information.

TV promotions have become a cornerstone of the pharmaceutical business since regulators opened the floodgate a decade ago. Companies spent roughly $3.5 billion on spots last year.

But some lawmakers and consumer advocates say the ads can encourage over-prescribing of medications before all their side effects are known. By encouraging patients to report negative reactions to the FDA, they hope regulators will be able to catch drug safety problems sooner.

"Drugs get approved based on results of a small number of people in clinical trials, but it's really when millions of people start taking them that we see side effects that might not have been known to the company," said Kim Witczak, founder of patient advocacy group WoodyMatters. The group is named for Witczak's husband, Woody, who committed suicide in 2003 while taking Pfizer's antidepressant Zoloft. The next year, the FDA added warnings about risks of suicidal behavior to all depression drugs.

A Consumer Reports poll published this year found only 35 percent of consumers knew they could report drug side effects to the government.

Print advertisements already include FDA contact information, as required by a law passed last fall. The legislation ordered the FDA to report to Congress by late March whether that information should also be mandatory for TV ads.

An agency spokeswoman said it submitted an interim study to lawmakers but is still working on the final report.

The Pharmaceutical Research and Manufacturers of America have not yet taken a stance on the issue. However, the group -- which represents Merck & Co. Inc., Wyeth and other drugmakers -- supported adding the language about side effects to print advertisements.