The broad-spectrum antibiotic Cipro and similar quinolones kill bacteria by destroying the bacterium's little ring of DNA, and they are very effective.  They are widely prescribed for anthrax exposure and to women for urinary tract infections.  However, your body's mitochondria, the source of energy for all cells, has almost identical DNA rings, and this family of antibiotics also destroys those rings and takes out the mitochondria.  Here is a LINK to a list of quinolones.

    Healthy mitochondria are a key ingredient to a healthy lifespan, and I do not want mine destroyed.  Therefore, I plan to put in my medical records a note that says that quinolones should not be prescribed.