OMAHA, Neb. -- The avian flu scare is fueling demand for the prescription drug Tamiflu, so much so that an Omaha pharmacy temporarily ran out last week.

Some scientists think the antiviral drug might be effective against the bird flu. Word has gotten out about that theory, even though the government has said it is not 100 percent clear the Tamiflu would work against the avian flu, reported television station KETV in Omaha.

Many people are buying it anyway. Pharmacists worry the high demand could cause problems during the regular flu season.

Pharmacists said there will be plenty of vaccine, but if a person is looking for Tamiflu, that person may have to call around.

"We've been able to buy and order on a daily basis," Randy Paulsen, of Roger's Pharmacy, said last week. "Today was the first day we were temporarily out of stock."

Tamiflu is an antiviral tablet used to treat flu symptoms. Paulsen said that during a regular flu season, he sells about six boxes a week.

"(That's) about a tenth of what we're selling so far this season," he said.

He's filling 15 to 20 Tamiflu prescriptions a day. Paulsen thinks a lot of people are buying Tamiflu because of fears of an avian flu outbreak. Some studies show Tamiflu can prevent the virus from reproducing, but that's only a handful of cases.

Not only are people stockpiling the drug, some are trying to make a profit. Tamiflu normally sells for about $70 a box for 10 tablets. Last week, someone tried to sell a box for $174 on eBay, but the ad was yanked because that is something the online auction house doesn't allow.

Doctors are urging people not to hoard the medication because it will be needed during flu season.

"Maybe it's nice to have on hand, but we don't know if it's effective against the avian flu," Paulsen said.

Other pharmacies in Omaha are experiencing the same rush that Paulsen is. But that does not equal a shortage of Tamiflu, and pharmacists expect to stock more soon.

The Swiss drug company Roche Holding said it's building a new manufacturing plant in the United States to boost production of antiviral drugs in case there's a pandemic.