Sprout Pharmaceutical, maker of drug flibanserin designed to increase libido in women, said it has hit a roadblock with the Food and Drug Administration (FDA) in its attempt to create a female Viagra, according to MSN News last Wednesday, December 11.

The FDA questions Sprout if flibanserin's benefits outweigh its risks, noting the drug's modest effectiveness. The FDA also pointed out that flibanserin causes fatigue, dizziness and nausea, the report said.

The pharma company said it will appeal the October letter it received from the FDA that denied flibanserin's approval. However, the chance for Sprout's appeal to get an approval looks slim. According to government figures, the FDA denied 14 out of 14 appeals last year.

The report said that the FDA's letter to Sprout Pharmaceutical is the latest among the many challenges for pharm companies trying to develop drug therapy treatment for women. Drugs designed to address women's libidinal problems among women is an untapped market. After Viagra's success in the late 1990s, may pharma companies tried to replicate it, but this time to address women libidinal problems. Viagra is a drug created to treat erectile-dysfunction by increasing blood flow men's genitals.

However, drugs like flibanserin deals with women's libidinal problems differently. Among men, increased libido means enhancement in sexual performance, but for women, the lack of libido often leads to stress. Doctors and experts agree that most women's sexual desires are psychological. Thus, doctors need to consider different causes that stress women out. For doctors and experts, extreme care must be taken before treating women with sexual desire disorders, which often include hormonal disorders, relationship problems, depression and mood swings that may be caused by other medications.

"Erectile dysfunction is a really easy thing to measure," Kim Wallen, a researcher from Emory University, told MSN News. "Motivation is a hard thing to measure and, quite honestly, we don't know enough about what creates sexual motivation to manipulate it."