A patient information sheet comes with prescription medications. A recent Food and Drug Administration study found that only 8 percent of the information sheets are easy to read and comprehensible. Tiny fonts and close margins are only part of the problem. KY3 News' investigation found they may not list critical information needed to keep people safe.

Just a year ago, playing calmly with his brother was a chore for Cooper Norman, 6. He was often agitated, easily frustrated and, on some occasions, violent.

”He started hitting me and kicking and screaming at me to the point where I had to lock myself in the bathroom,” said Cherie Norman, Cooper’s mother.

The Normans were close to getting professional help and some serious medication for Cooper when they saw a story on KY3 News about the asthma medication Singulair possibly causing behavioral problems in children. Soon after, Norman and Cooper's doctor took Cooper off Singulair and his behavior improved dramatically.

“He is the most loving, affectionate, positive child,” said Nrman.

The patient information sheet that you receive with prescription medication is supposed to include possible side effects and other helpful information. The leaflet that Norman received with Cooper's Singulair prescription said nothing about suicidal thoughts as a side effect.

”Parents have a right to know this,” she said.

Since her son went off the medication, more pharmacies have begun warning consumers of possible behavioral changes associated with the medication but some still don't. The reason is the FDA doesn't regulate the patient information sheets that come with any prescription medication.

“The FDA provides broad guidance on what leaflets should contain but the FDA does not approve leaflets,” said Terry Barks of St. John’s Hospital’s Drug Information Center.

Instead, pharmacies rely on third-party vendors to take the information that they deem most important from the drug's manufacturer, condense it and make it understandable to consumers. As a result, Barks says information sheets for the same medication may not include the same information at every pharmacy.

”At present, they don't uniformly contain all the information experts believe they should contain in the way of warnings and precautions,” said Barks.

To see how much the package inserts can vary, a reporter went to six pharmacies and requested a medication information sheet for Singulair. Five of the six inserts do include mental and mood changes as a possible side effect. One still doesn't. Our investigation found there are other side effects also not listed on all the inserts.

Just five of the inserts list irregular heartbeat as a possible side effect; four say the medication can cause dark urine; three list diarrhea, mouth pain, nausea or vomiting; only two specifically list agitation, nervousness and depression. In fact, of the 40 side effects listed on Singulair's Web site, just 11 – or about 25% - were listed on the inserts from all six of the pharmacies.

”That's not fair. That's not fair to anyone taking medications,” said Norman.

The FDA recognizes the problem. The recent FDA study found just 75 percent of patient information sheets were considered useful information.

”The FDA proposed to regulate it back in the ‘90s and it was Congress that decided we didn't need regulation,” said Barks.

Pharmacist Gary Grove recognizes that the information sheets can vary from pharmacy to pharmacy but says it would be impossible to list every piece of information about a drug on one leaflet.

”It might take 20-30 or 50 pages of printout to list every side effect that could happen,” said Grove.

He says vendors do a good job of listing the most common and serious side effects, and patients should understand, if they experience anything unusual while taking a medication, they should call their doctor or pharmacist, regardless of what's listed on the patient information sheet.

The Web sites of most drug manufacturers list every piece of information you could ever want about the prescription, so going there is always a good idea. Also, in regards to Singulair, while the FDA and Merck are both still investigating, leadership from the American Academy of Allergy Asthma and Immunology says there is no data to indicate a link between Singulair and suicide.