A bottle of Viagra pills is seen in an undated file photo. The mayor of a small Brazilian town has begun handing out free Viagra, spicing up the sex lives of dozens of elderly men and their partners. [Reuters]

Brasilia - The mayor of a small Brazilian town has begun handing out free Viagra, spicing up the sex lives of dozens of elderly men and their partners.

"Since we started the free distribution of sexual stimulants, our elderly population changed. They're much happier," said Joao de Souza Luz, the mayor of Novo Santo Antonio, a small town in the central state of Mato Grosso.

Souza Luz said 68 men over the age of 60 had already signed up for the program, which was approved by the town's legislature and has been dubbed "Happy Penis," or "Pinto Alegre" in Portuguese.

But the program has also had the unforeseen consequence of encouraging some extra-marital affairs, Souza Luz said.

"Some of the old men aren't seeking out their wives. They've got romances on the side," he said.

To discourage such illicit canoodling, Souza Luz said the city had decided to begin distributing the Viagra pills to the wives of the men who signed up for the program.

"That way, when the women are in the mood, they can give the pills to their husbands," he said.