<<Disclaimer: Verify this information before applying it to your situation.>> Hi Listmates, I had been taking doxycycline when I went to the dentist but now I found out it is not g/f. No wonder I didn't feel good after taking the 2 pills. Any suggestions on an antibiotic that is NOT penicillin or related that I could take when I go to the dentist because of my mitral valve prolapse? Any suggestions would be appreciated. Thanks in advance. Rosalie