In terms of differences, eukaryotic cells are much larger and more complex than prokaryotic cells. On average, a typical eukaryotic cell is about 1,000 X larger in volume than a typical prokaryotic cell.
This means both drugs (amoxicillin and penicillin) can treat a wide variety of infections. However, unlike amoxicillin and penicillin, the routinely prescribed drug, metronidazole, has a more selective action towards anaerobic bacteria. These bacteria are the ones causing the signs and symptoms of bacterial vaginosis.
Oral or vaginal metronidazole and vaginal clindamycin cream cure bacterial vaginosis in as many as 8 out of 10 cases. Although medicine usually cures bacterial vaginosis, it often comes back. Some doctors have women use medicine for a longer time to prevent this.