<unk>  is a antiprotozoal, antibacterial agent and nitroimidazole that is FDA approved for the treatment of trichomoniasis, giardiasis, amebiasis, bacterial vaginosis. There is a Black Box Warning for this drug as shown here.  Common adverse reactions include metallic/bitter taste, nausea, weakness/fatigue/malaise, dyspepsia/cramps/epigastric discomfort, vomiting, anorexia, headache, dizziness and constipation.
Tinidazole
Secnidazole
Clomidazole
Benznidazole
Ornidazole
Propenidazole
Metronidazole 
Nitazoxanide