If Viagra, Levitra or Cialis doesn't make the good times roll, there's help on the way.

The U.S. Food & Drug Administration announced Friday it had approved a new drug to treat erectile dysfunction. The medical establishment's name for trouble getting and keeping an erection, erectile dysfunction, or ED, effects an estimated 30 million men in the United States.

Stendra, marketed by a Silicon Valley firm, Vivus Inc., requires patients to take it 30 minutes before sexual activity, the FDA said. Viagra can take up to 60 minutes to work, according to the manufacturer's website. Doctors should prescribe the lowest dose of Stendra necessary to be, ahem, effective.

"This approval expands the available treatment options to men experiencing erectile dysfunction," said Victoria Kusiak, M.D., deputy director of a drug evaluation office in the FDA's Center for Drug Evaluation and Research.

Stendra belongs to a class of drugs which are used to help increase blood flow to the penis. The FDA said Stendra, like other ED drugs, should not be used by men who also take nitrates, commonly used to treat chest pain, because the combination can cause a sudden drop in blood pressure.

The most common side effects reported in greater than two percent of patients in clinical studies of Stendra included headache, redness of the face and other areas, nasal congestion, common cold-like symptoms and back pain, the FDA said. In rare cases, some patients taking Stendra and other ED drugs may get an erection lasting longer than four hours, in which cases they should seek immediate medical care.

FDA spokeswoman Stephanie Yao said Stendra's "safety and efficacy" were established in three clinical studies involving 1,267 patients who were randomly assigned to take Stendra for up to 12 weeks at does ranging from 50 to 200 milligrams. A subset of the larger group of patients were enrolled in another trial to receive up to an additional 40 weeks of treatment. Results showed that the side effects commonly reported in patients using Stendra did not worsen over time.

As is the case with other ED drugs, the FDA warned patients who experience a sudden loss of vision or hearing to stop taking the drug and call a doctor right away.

Contact Michael Hinkelman at 215-854-2656 or @mhinkelman on Twitter.