A new prescription drug called Addyi, which received federal approval last Tuesday, could help women with low sex drive, but Minnesota doctors remain concerned about risks and expectations over a pill that has been dubbed “female Viagra.”

The nickname is a misnomer because Addyi needs to be taken daily — unlike Viagra, which men take before sex to treat erectile dysfunction, said Dr. Carrie Terrell, an obstetrician at the University of Minnesota Medical Center.

“It’s not like Viagra,” she said. “It’s more like an antidepressant in that way.”

While Viagra works by increasing blood flow to the penis, Addyi works over time by triggering the brain’s release of chemicals that stimulate sex drive. Addyi, which will be in pharmacies this fall, isn’t approved for menopausal women, and that rules out a significant portion of women reporting low libido. It also comes with a warning about the risk of low blood pressure and fainting if taken with alcohol.

Terrell said she would prescribe it for women after addressing other problems leading to a lack of sex, including relationship issues. “We have to sort out the stress disorders, and sleep deprivation and fatigue,” she said.

Dr. Jewelia Wagner of Clinic Sofia in Edina doesn’t intend to prescribe Addyi until more safety data emerges and advice comes from groups such as the American Congress for Obstetricians and Gynecologists.

The U.S. Food and Drug Administration twice denied Addyi before last week’s approval. The drug’s effectiveness was based on a study of 5,000 patients, but only 850 took it for more than one year. “The bottom line is it’s too new,” Wagner said.

Patients have already mentioned it though, and Wagner is excited that the news is stimulating talk about a sensitive issue. Skeptics have questioned whether low libido in women is a condition in need of medication, but Wagner called it a “true problem.”

The news “has opened the doors up to women coming into our office and feeling comfortable talking about their low sexual desire,” she said. “It causes a problem in intimacy and relationships and it needs to be discussed.”

Optimal treatment for some women could mix medication with talk therapy, she said.

Terrell said women need realistic expectations about the drug, which in a clinical trial added about two sexual encounters per month on average. That might not mean as much for women in relationships who went from having sex three times per month to five times. However, it could be very meaningful for women who went from no sex to two encounters per month.