I've had to take Flagyl a number of times after antibiotics when my normal flora gets messed up. Also meds for yeast overabundance. This summer I had so many antibiotics that my lymph nodes in my abdomen got enlarged and I thought I had appendicitis or something. The surgeon I went to poked the lumps with his finger and said "What'd they try to do, sterilize you?", then laughed. He told me to let nature take it's course and in about 6 weeks I was feeling lots better.When on Flagyl you might have a metallic taste in your mouth and or headaches. These are just side effects and go away when the Flagyl is finished. My face even gets a little puffy, but what're ya gonna do? Good luck and hope you feel better soon.