- Use of doxycycline might increase the incidence of vaginal yeast infections. To prevent a vaginal yeast infection, consider eating yogurt with live cultures (e.g., acidophilus) or douching with plain yogurt with live cultures or taking oral acidophilus tablets or probiotic suppositories while taking doxycycline.
- Use of doxycycline may reduce the effectiveness of oral contraceptive pills, according to the FDA. Use a backup form of pregnancy prevention while on doxycycline. We recommend that you always use condoms to reduce your risk of sexually transmitted infections.