Fast-acting Viagra spray developed

A spray could have a faster effect than a pill

Impotent men could benefit from Viagra in five to 10 minutes instead of up to an hour by taking the drug through the nose, researchers say.

They have developed a nasal spray form of the anti-impotence drug that they say works up to 12 times faster than the average pill.

They also said that the faster action would prevent users taking a double dose of the drug, which could lead to harmful side effects.

Nasal delivery

Professor Anwar Hussein, a researcher at the University of Kentucky College of Pharmacy, said he and Professor Lewis Dittert developed the nasal spray.

He said they have patented the technology and want to license it to Pfizer.

"Sometimes patients taking Viagra are embarrassed because they wait an hour or longer and still there's no effect, especially if they've taken the pill with meals," Professor Hussein.

Frustrated patients then sometimes take another pill in an attempt to speed the effect. This creates the risk of adverse side effects, Professor Hussein said.

Since Viagra went on the market last year, approximately 130 men have been reported to have died after taking it.

Key

Viagra's licence advises users to wait up to an hour for results

"The key" to the nasal spray "was to find how to make Viagra very water soluble so the dissolved drug can be used through the nose", Professor Hussein said.

They tested nasal drops in rats and found that it took effect "within five to 10 minutes", Professor Hussein said.

"Our version will be so quick and convenient to use and would definitely be more popular than the pills, which just take too long to work."

He said he wants Pfizer to take up the licence and start tests of the spray on humans.

Romance

But Pfizer, the company that makes Viagra, said that it had not received complaints about the drug's speed of action.

Andy Burrows, a spokesman for the company, said the researchers were operating entirely independently of the company.

He said the company had no plans to develop a faster working form of the drug.

Although Viagra's licence says that users should allow up to an hour for it to take effect, performance depended on the individual and could be as fast as 20 minutes, he said.

But the company was working on a wafer form which, although no faster than the pills, would be easier to ingest, he said.

"You have to compare what Viagra offers with what was on offer before. That is, an injection in the penis or a pellet that you have to stick into the urethra and massage for 10 minutes," he said.

"Then instantly you get the sexual stimulation no matter what, without the romantic side."

"With Viagra you may have to plan ahead a little bit but it creates a much more natural response than anything else that's around."

"You have to compare it with what there was before," he said.

He added that it was unusual but not unheard of for researchers to set to work on a company's product independently.

However, when it did happen, it was usually when the patent on a product was about to expire.

The UK government, which has placed a temporary ban on NHS prescription of Viagra, is due to announce guidelines on its use next week.