Ive taken antibiotics for a dental infection that caused an abscess. The pain of that made sure I took them all as directed. Ive taken many many different kinds of antibiotics over the years and only 1 kind ever made me feel n* but I didnt v* thankfully. Most recently I took a combination of 2 high dose antibiotics (3000mg 4 times a day for a week) for a h-pylori infection. If anything was going to cause problems that would have. My advice would be take them as directed & finish the course. Any infection if left untreated could spread throughout your body & make you feel dreadful.