Levofloxacin is a drug used in the treatment of bacterial infections. It belongs to a class of drugs known as quinolones, which exert their effects by interfering with bacterial DNA synthesis. Common side effects associated with levofloxacin use include nausea, vomiting, constipation and heartburn.Levofloxacin is an antibacterial medication used to treat a broad range of bacterial infections. In many cases, the drug is used to treat anthrax or plague. Levofloxacin works by killing sensitive bacteria cells causing infections. It also inhibits the growth of the bacteria cells, and this slows the spreading the infection. With the spread of the infection slowed, the immune system is given time to attack the bacteria and treat the affected part of the body. Some of the conditions that are Levofloxacin can treat includes Bronchitis, pneumonia, sinusitis, cystitis and prostatitis among others. The drug is supplied in solution form, and it can be taken orally or as an IV injection. Levofloxacin is associated with several side effects including nausea and headache.