My bf was perscribed Penicillan to treat his Trichomonias. But I was perscribed Metronidazole to treat my Trichomoniasis ( I am not pregnant). We each went to our own (diffrent) family doctors. I only know that taking Tinidazole or Metronidazole (Flagyl) can cure Trich. Is his doctor wrong to prescribe Penicillan to treat his Trichomonias?