The US Food and Drug Administration (FDA) has approved the first drug on the market designed to boost female libido.The approval came with a warning about potentially dangerous side effects.

The drug, to be sold under the trade name Addyi, has been nicknamed “female Viagra” in media reports, even though it does not work like the blockbuster pill for men.

The female drug’s label will bear a boxed warning alerting doctors and patients that combining the pill with alcohol can cause dangerously low blood pressure and fainting.

That same risk can occur when taking the drug with other commonly prescribed medications.

Doctors will only be able to prescribe it after completing an online certification process that requires counselling patients about Addyi’s risks.

“Patients and prescribers should fully understand the risks associated with the use of Addyi before considering treatment,” said Dr Janet Woodcock, director of the FDA’s drug centre.

The pink little pill works on the brain, unlike Viagra, which affects blood flow to the genitals.

The drug, flibanserin, is designed for premenopausal women whose lack of sexual desire causes distress.

But it is controversial.

Advocates say the increase in sexual desire observed during a clinical trial is meaningful, while opponents say the drug is not worth the side effects, which also include nausea, drowsiness and dizziness.

“This is not a drug you take an hour before you have sex,” Leonore Tiefer, a psychologist and sex therapist who called on the FDA to reject the drug, told the AP news agency.

“You have to take it for weeks and months in order to see any benefit at all.”

The FDA had twice rejected the drug, which is made by Sprout Pharmaceuticals.

The turnaround came after an advisory panel concluded in June the drug should be approved with strict measures in place to ensure patients are fully aware of the risks.