Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Heartburn Drugs May Neutralize Plavix
U.S. health officials are studying reports that the action of the popular blood thinner Plavix can be neutralized by some heartburn medications, the Associated Press reported.
Plavix, used to prevent deadly blood clots, has been prescribed to more than 90 million people worldwide. Because it can upset the stomach, Plavix (generic name clopidogrel) is often prescribed with heartburn drugs called proton pump inhibitors.
A few months ago, researchers reported that patients taking Plavix and these heartburn drugs had a significantly increased risk of hospitalization for chest pain, heart attack or stroke. The heartburn drugs may interfere with a liver enzyme need to metabolize Plavix, the researchers suggested.
In a statement, the U.S. Food and Drug Administration said it's important to fully understand the interaction between Plavix and proton pump inhibitors. The FDA also said there's no evidence that another family of heartburn drugs called H2 blockers interfere with Plavix, the AP reported.
For now, patients should continue taking Plavix but doctors should be cautious when prescribing heartburn drugs to patients taking the blood thinner, the FDA said.
Imported Diet Pills May Contain Amphetamines: Study
Consumers and doctors need to know that illegal diet pills from South America may contain amphetamines, warns a U.S. physician.
The majority of amphetamine-based diet suppressants have been banned in the United States, but many are still prescribed in South America and other parts of the world, said Dr. Pieter Cohen, of Cambridge Health Alliance and the Harvard Medical School, United Press International reported.
He said many American doctors aren't aware of these diet pills and need to know about the number of serious side effects they can cause in order to identify and treat patients with unexplained symptoms, such as chest pains, palpitations, headaches and insomnia.
In his study, Cohen reviewed two case reports of patients who took illegal diet pills that contained amphetamines. In one case, a woman's mysterious symptoms stopped after she stopped taking imported diet pills. The second case involves a man suspended from work after testing positive for amphetamines he ingested while taking imported diet pills, UPI reported.
The study appears in the Journal of General Internal Medicine.
Drug Giant Pfizer to Buy Rival Wyeth
Pfizer Inc., the world's largest pharmaceutical company, has announced an agreement to buy one of its rivals, Wyeth, for $68 billion, the Wall Street Journal reports.
Wyeth's biggest over-the-counter seller is the pain medication Advil (ibuprofen), which is the largest OTC ibuprofen brand sold in America. Its prescription drugs include the anti-depressant Effexor, acid reflux inhibitor Protonix, the pneumococcal vaccine Prevnar and the female hormone replacement drug Premarin.
Pfizer's drugs also often dominate the market and include Benadryl for allergies, Celebrex for pain, Lipitor for cholesterol control, Glucotrol for type 2 diabetes, Viagra for erectile dysfunction and Zoloft for depression.
While this one of the largest buyouts among pharmaceutical companies on record, it isn't the biggest, the Journal reports. In 2000, Glaxo Wellcome PLC acquired SmithKline Beecham PLC for $76 billion.
Fifth Victim Dies From Avian Flu in China
An 18-year-old man died from bird flu Monday in southern China, the fifth human death from the virus in the country this year, according to state media reports.
But, according to the Associated Press, the country's Health Ministry said after the earlier deaths this month that there is no evidence of a large-scale outbreak of bird flu. It called the illnesses isolated and unrelated.
The fourth victim, a 31-year-old woman from the western part of the country, died Friday, Associated Press reported.
Both victims died from the H5N1 strain of bird flu, the same strain that has caused the deaths of 251 people since the World Health Organization (WHO) started keeping statistics in 2003.
The other three deaths appear not to be related, AP reported, coming in three different geographic regions. As in all other human cases reported by WHO, this incident of bird flu appeared to be contracted by contact with poultry or fowl and not transmitted from human to human.
Scientists have been carefully monitoring avian flu outbreaks, in which millions of birds have been put to death, to see whether the H5N1 virus has mutated. The fear is that a mutation causing human-to-human infection could lead to a worldwide influenza pandemic.
Study Supports Safety of Vaccine Ingredient Thimerosal
A new study offers more proof that thimerosal -- a mercury-based preservative once used in many vaccines -- poses no threat to children's brains. There has been intense debate about whether thimerosal causes autism, a link repeatedly discounted in scientific studies.
The new study included 1,403 Italian children who were given vaccines in the early 1990s and underwent brain function tests 10 years later. Those tests showed no signs of problems and only one case of autism was identified, the Associated Press reported.
The findings appear in the February issue of the journal Pediatrics.
"Put together with the evidence of all the other studies, this tells us there is no reason to worry about the effect of thimerosal in vaccines," said lead author, Dr. Alberto Tozzi of Bambino Gesu Hospital in Rome, the AP reported.
The study was welcomed by outside experts.
"It's yet another well-done, peer-reviewed research study that has demonstrated there is no risk of any neurodevelopmental outcomes associated with thimerosal in vaccines," University of Pennsylvania epidemiologist Jennifer Pinto-Martin told the AP.
Sexual Activity Linked to Prostate Cancer Risk: Study
The more sexually active a man is in his 20s and 30s, the greater his risk of prostate cancer, suggests a U.K. study that included 400 prostate cancer patients and 409 men without the disease.
The men were questioned about their sexual behaviors while younger. About 40 percent of the prostate cancer patients had had at least six female sexual partners, compared with less than a third of the cancer-free men, BBC News reported.
The Nottingham University study found that 40 percent of the prostate cancer patients were sexually active (masturbation or sex) at least 20 times a month or more in their 20s, compared with 32 percent of those without prostate cancer.
It's possible that higher levels of sex hormones could be the cause of a higher sex drive and increased prostate cancer risk, said the researchers. The study appears in the journal BJU International.
While the study is useful, more research is needed, John Neate, chief executive of The Prostate Cancer Charity in the U.K., told BBC News.
"The role of sexual activity is becoming an increasing focus for prostate cancer research, but unfortunately this study does little to offer any practical advice to men wishing to reduce their risk of the disease," Neate said.