TUESDAY, May 31 (HealthDay News) -- Dificid (fidaxomicin) has been approved by the U.S. Food and Drug Administration to treat diarrhea associated with Clostridium difficile infection.

The bacterial illness, commonly acquired by the elderly and others with weakened immune systems in hospitals and group settings, is abbreviated C. diff. It is easily passed from person to person by touching contaminated surfaces, the FDA said in a news release.

The infection frequently causes diarrhea, can lead to colitis and other intestinal conditions, and may cause death in severe cases, the agency said. In some people, the illness can recur.

Dificid was evaluated in clinical studies involving 564 people with C. diff -associated diarrhea. More people who took Dificid were still symptom-free three weeks after stopping treatment than those who took a common antibiotic, vancomycin, the FDA said.

Recommended dosage with Dificid is twice daily for 10 days. The most common side effects reported included nausea, vomiting, headache, abdominal pain and diarrhea.

Dificid was developed by Optimer Pharmaceuticals, based in San Diego.

More information

To learn more about this illness, visit the U.S. Centers for Disease Control and Prevention.