Health Highlights: June 28, 2005
Pfizer: No Link Between Viagra and Blindness Ointment May Soothe Psoriasis Birch Candles Recalled for Fire Hazard Vitamin C Doesn't Prevent Colds: Study WHO Concerned About Avian Flu Outbreak Among Birds in China Canada Plans Limits on Drug Sales to U.S.
Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Pfizer: No Link Between Viagra and Blindness
There's no evidence that taking Viagra increases the risk of blindness, Pfizer Inc., the maker of the anti-impotence drug, said late Monday.
The company said it reached that conclusion after it reviewed all post- marketing "ocular events" among Viagra users, the Associated Press reported.
"After more than 10 years of rigorous clinical study and worldwide safety monitoring of a medicine used by more than 27 million men, there is no evidence to suggest a link between Viagra and blindness or other serious ocular events," said Dr. Joseph Feczko, chief medical officer at Pfizer.
"In addition, several studies specifically looking into the effect of Viagra in the eye by Pfizer as well as independent ophthalmologic experts found Viagra to have no serious adverse effects in the eye," Feczko said.
The U.S. Food and Drug Administration is investigating about 50 reports of Viagra users who suffered vision loss.
Pfizer said most of the reported cases of non-arteritic anterior ischemic optic neuropathyone (NAION) in Viagra users occurred in people with underlying risk factors associated with development of NAION, the AP reported.
NAION is one of the most common acute optic nerve diseases in older adults.
Ointment May Soothe Psoriasis
A skin ointment containing dithranol may soothe psoriasis by killing the cells that actually cause the problem, according to British researchers at Newcastle University.
Dithranol is derived from the araroba tree found in the Amazon rain forest. The drug must be administered carefully since it can cause skin burning and clothing discoloration if misused, BBC News Online reported. It's currently only used in hospitals for severe cases of the autoimmune skin disease, the network reported.
Psoriasis, caused by the body's overproduction of skin cells, is characterized by red, scaly patches. The genetic disorder is typically found on the elbows, knees, scalp and lower back, although it can occur on any area of the skin.
An estimated 2.1 percent of Americans have psoriasis, including 4.5 million adults. While it can affect people of any age, it most often strikes those between 15 and 35, the National Psoriasis Foundation says.
Birch Candles Recalled for Fire Hazard
Target stores are recalling some 230,000 birch and bark candles that pose a fire hazard, the U.S. Consumer Product Safety Commission says.
The company has 18 reports of the bark surrounding the candles catching fire, including five reports of property damage. No injures have been reported.
The creme-colored candles were available in four sizes, from 3-inches-by-3-inches to 6-inches-by-6-inches. They were sold from September 2004 through January 2005 at Target stores nationwide for between $6 and $15.
Consumers can return the candles at any Target store for a gift card for the full value. For more information, contact Target at 1-800-440-0680.
Vitamin C Doesn't Prevent Colds: Study
There's no proof that high doses of vitamin C are effective in preventing colds or reducing symptoms, says a study in the journal Public Library of Science Medicine.
The study authors concluded that the only times that vitamin C may be effective against colds are in cases of extreme physical exertion such as running marathons in winter, Toronto's The Globe and Mail newspaper reported.
Australian and Finnish researchers reviewed 59 studies conducted between 1940 and 2004 -- including 23 that examined the ability of vitamin C to prevent the common cold in the general population. Those studies found that vitamin C had virtually no effect.
Six of the studies included athletes and soldiers under extreme physical stress while taking part in running or ski marathons or doing winter training exercises. In this small group of people in these particular circumstances, vitamin C reduced the rate of colds by about 50 percent.
The review also included studies that looked at whether large doses of vitamin C shorten the length of colds. The review concluded there were no benefits for adults who took large doses (10 grams per day) of vitamin C for the first three days of a cold, The Globe and Mail reported.
However, there was some evidence that large doses of vitamin C may reduce symptoms in children. The researchers said new studies should look specifically at this issue.
WHO Concerned About Avian Flu Among Birds in China
An outbreak of bird flu among migratory birds in northern China is far more serious than previously believed and has United Nations health experts concerned, BBC News reported.
So far, about 5,000 birds have died in Qinghai province. That toll is about five times greater than the estimate given by China.
"The virus has obviously changed to be more pathogenic to animals. What it means to humans we don't know," said World Health Organization (WHO) official Henk Bekedam.
This outbreak at Lake Qinghai is especially troubling because it involves migratory birds.
"The biggest concern I would have is that we have many birds that are asymptomatic and they can fly from here to 1,000 km (621 miles) further up. That's troublesome," Bekedam said.
It's critical that China conduct more tests on the birds before they begin to migrate to other areas, the WHO said. China has cordoned off a 30-mile radius around Lake Qinghai and nature reserve, BBC News reported.
Canada Plans Limits on Drug Sales to U.S.
Canada will announce plans this week to limit bulk sales of prescription drugs to the United States, Toronto's Globe and Mail newspaper reported Monday.
As more and more Americans buy their medications from Canadian sources at cheaper prices, Canadian officials are worried about the possibility of domestic shortages, the newspaper said. A ban on bulk shipments could also thwart retaliation from U.S. drug companies that have threatened sanctions against Canadian sources that mail prescription drugs back to the United States.
Canadian Health Minister Ujjal Dosanjh also will announce plans later this week to crack down on Canadian doctors who co-sign prescriptions for American customers, the newspaper reported.
In 2004, Americans bought an estimated $800 million worth of prescription drugs from Canadian sources -- largely via the Internet, the Globe and Mail said. The medicines from Canada are up to 80 percent cheaper than the American equivalents due to Canadian price controls.