ATLANTA (CNN) -- Nonprescription pain relievers can become dangerous -- even deadly -- when consumed with large amounts of alcohol.

To protect consumers, a new ruling by the U.S. Food and Drug Administration (FDA) requires all over-the-counter pain relievers and fever reducers to carry warning labels.

Products containing acetaminophen must alert users who are daily, heavy drinkers that they risk liver damage if they take the drug, while products containing aspirin and ibuprofen must warn of the potential danger of stomach bleeding.

Any products with more than one of the ingredients must warn heavy drinkers of both health risks.

The FDA defines a heavy drinker as someone who consumes three or more drinks daily.

Since 1993, any new pain or fever product has had to carry a generic warning for heavy alcohol users, but the new FDA ruling requires all nonprescription pain relievers to provide specific warnings of the possible side effects.

The FDA has given pharmaceutical companies six months to comply.

Food and Health Correspondent Holly Firfer contributed to this report.