Health Highlights: May 22, 2008

• Pilots, Air Traffic Controllers Can't Use Smoking-Cessation Drug
• Merck Halts Cholesterol Drug Study
• Brain Protein Linked to Addiction
• Bush Signs Bill Banning Genetic Discrimination
• Merck Settles State Suits Over Vioxx Ads
• Lower-Income Children Visit E.R. More Often

Here are some of the latest health and medical news developments, compiled by editors of HealthDay:

Pilots, Air Traffic Controllers Can't Use Smoking-Cessation Drug

Pilots and air traffic controllers will no longer be permitted to use the smoking cessation drug Chantix because it may cause side effects that could threaten aircraft safety, the U.S. Federal Aviation Administration said Wednesday.

The decision was based on emerging data about the drug, said FAA spokeswoman Laura Brown. For example, a report from the Institute for Safe Medication Practices said Chantix was linked to a number of health and safety problems, including accidents and falls, potentially lethal heart rhythm disturbances, heart attacks, seizures, diabetes and various psychiatric troubles, The New York Times reported.

In February, the U.S. Food and Drug Administration issued a public health advisory warning that some people taking Chantix had developed serious psychiatric symptoms and some had committed suicide.

The FAA will inform the 150 pilots and 30 air traffic controllers known to be using Chantix that the drug is no longer acceptable and they should stop using it, the Times reported. The agency will also notify associations representing commercial and private pilots that the drug is no longer permitted.

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Merck Halts Cholesterol Drug Study

A study of the experimental cholesterol drug MK-0524A has been halted by Merck & Co., three weeks after the U.S. Food and Drug Administration refused to approve the drug.

Merck, which hasn't revealed why the FDA rejected the drug, said the agency's decision didn't influence the cancellation of the ACHIEVE study, the Associated Press reported.

The study was stopped on the basis of data from previous studies of various cholesterol drugs that suggested ACHIEVE wouldn't be able to determine if the new drug would do much to prevent plaque build-up in the arteries of patients who have high cholesterol levels due to genetic factors, according to Dr. Yale Mitchel, vice president of cardiovascular disease at Merck Research Labs.

Some experts criticized the drug maker's actions.

Merck's explanation isn't satisfactory and it's not appropriate to halt medical experiments on human volunteers "without proper cause," Dr. Steven Nissen, chairman of cardiovascular medicine at the Cleveland Clinic, told the AP.

"I am concerned whether the reasons for terminating this trial are commercial or scientific," Nissen said.

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Brain Protein Linked to Addiction

A brain protein called DARPP-32 appears to play a role in addiction, according to a French study in the journal Nature.

Cocaine and other addictive drugs work by increasing levels of a messenger chemical called dopamine, which stimulates the brain's "reward" center. The French team found that DARPP-32, which helps the dopamine signaling process, built up in the part of the brain called the striatum when normal mice were given cocaine, amphetamine or morphine, Agence France-Presse reported.

The researchers then created genetically modified mice that produced a slightly altered form of DARPP-32 and found that the drugs had much less effect on these mice than normal mice in terms of impaired movement and drug cravings.

The results suggest that developing a drug that blocks DARPP-32 accumulation in the brain may prove useful in treating addiction and certain kinds of mental illness in which dopamine may play a role, AFP reported.

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Bush Signs Bill Banning Genetic Discrimination

A bill to protect people against job dismissal or from losing their health insurance based on genetic testing results was signed into law Wednesday by President George W. Bush.

Supporters of the Genetic Information Nondiscrimination Act gathered at the White House in support of the measure, which bars employers or insurers from discriminating against people whose genetic test results show they may be more susceptible to illnesses such as cancer and heart disease.