After an intense lobbying campaign, a federal advisory panel recommended approval of what would become the first drug to treat a lack of sexual desire in women.

The move was immediately hailed by some women’s organizations as a step toward sexual equality by, in effect, giving women their counterpart to Viagra, the widely prescribed drug for male erectile dysfunction.

By a vote of 18-6, the advisory committee to the Food and Drug Administration favored approval of the drug, flibanserin, for women whose lack of sexual desire was not attributable to other causes such as disease or relationship troubles, providing that certain steps were taken to limit the risks of the drug. Doctors might be required, for instance, to inform patients of potential side effects — like low blood pressure, fainting, nausea and dizziness — and physicians might have to become certified to prescribe the drug.

The controversial campaign by some women’s groups to win federal approval was waged under the banner Even the Score, which accused the F.D.A. of gender bias because it had approved Viagra and other drugs to help men have sex while leaving women without options. The participants in the campaign had been brought together by a consultant to Sprout Pharmaceuticals, the developer of flibanserin.